原文链接:
https://blog.csdn.net/weixin_41084236/article/details/81564963#001_18
python3.0 100例
Python3 100例
原题地址:
http://www.runoob.com/python/python-100-examples.html
git地址:
https://github.com/RichardFu123/Python100Cases
转载请标注:
https://blog.csdn.net/weixin_41084236/article/details/81564963
原例为Python2.7版本
重写过程中有不少是随意发挥的
重写运行版本:Python3.7
作者:Shawn
- 总的来说,并没有什么难度,全部搂了一遍也只花了不到2天时间,其中还有一半以上的时间是用来写文档的。
- 用来练练手还是凑合的。
文章目录
- Python3 100例
- 实例001:数字组合
- 实例002:“个税计算”
- 实例003:完全平方数
- 实例004:这天第几天
- 实例005:三数排序
- 实例006:斐波那契数列
- 实例007:copy
- 实例008:九九乘法表
- 实例009:暂停一秒输出
- 实例010:给人看的时间
- 实例011:养兔子
- 实例012:100到200的素数
- 实例013:所有水仙花数
- 实例014:分解质因数
- 实例015:分数归档
- 实例016:输出日期
- 实例017:字符串构成
- 实例018:复读机相加
- 实例019:完数
- 实例020:高空抛物
- 实例021:猴子偷桃
- 实例022:比赛对手
- 实例023:画菱形
- 实例024:斐波那契数列II
- 实例025: 阶乘求和
- 实例026:递归求阶乘
- 实例027:递归输出
- 实例028:递归求等差数列
- 实例029:反向输出
- 实例030:回文数
- 实例031:字母识词
- 实例032:反向输出II
- 实例033:列表转字符串
- 实例034:调用函数
- 实例035:设置输出颜色
- 实例036:算素数
- 实例037:排序
- 实例038:矩阵对角线之和
- 实例039:有序列表插入元素
- 实例040:逆序列表
- 实例041:类的方法与变量
- 实例042:变量作用域
- 实例043:作用域、类的方法与变量
- 实例044:矩阵相加
- 实例045:求和
- 实例046:打破循环
- 实例047:函数交换变量
- 实例048:数字比大小
- 实例049:lambda
- 实例050:随机数
- 实例051:按位与
- 实例052:按位或
- 实例053:按位异或
- 实例054:位取反、位移动
- 实例055:按位取反
- 实例056:画圈
- 实例057:画线
- 实例058:画矩形
- 实例059:画图(丑)
- 实例060:字符串长度
- 实例061:杨辉三角
- 实例062:查找字符串
- 实例063:画椭圆
- 实例064:画椭圆、矩形
- 实例065:画组合图形
- 实例066:三数排序
- 实例067:交换位置
- 实例068:旋转数列
- 实例069:报数
- 实例070:字符串长度II
- 实例071:输入和输出
- 实例072:创建链表
- 实例073:反向输出链表
- 实例074:列表排序、连接
- 实例075:不知所云
- 实例076:做函数
- 实例077:遍历列表
- 实例078:字典
- 实例079:字符串排序
- 实例080:猴子分桃
- 实例081:求未知数
- 实例082:八进制转十进制
- 实例083:制作奇数
- 实例084:连接字符串
- 实例085:整除
- 实例086:连接字符串II
- 实例087:访问类成员
- 实例088:打印星号
- 实例089:解码
- 实例090:列表详解
- 实例091:time模块
- 实例092:time模块II
- 实例093:time模块III
- 实例094:time模块IV
- 实例095:转换时间格式
- 实例096:计算复读次数
- 实例097:磁盘写入
- 实例098:磁盘写入II
- 实例099:磁盘读写
- 实例100:列表转字典
实例001:数字组合
题目 有四个数字:1、2、3、4,能组成多少个互不相同且无重复数字的三位数?各是多少?
程序分析 遍历全部可能,把有重复的剃掉。
total=0
for i in range(1,5):
for j in range(1,5):
for k in range(1,5):
if ((i!=j)and(j!=k)and(k!=i)):
print(i,j,k)
total+=1
print(total)
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简便方法 用itertools中的permutations即可。
import itertools
sum2=0
a=[1,2,3,4]
for i in itertools.permutations(a,3):
print(i)
sum2+=1
print(sum2)
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实例002:“个税计算”
题目 企业发放的奖金根据利润提成。利润(I)低于或等于10万元时,奖金可提10%;利润高于10万元,低于20万元时,低于10万元的部分按10%提成,高于10万元的部分,可提成7.5%;20万到40万之间时,高于20万元的部分,可提成5%;40万到60万之间时高于40万元的部分,可提成3%;60万到100万之间时,高于60万元的部分,可提成1.5%,高于100万元时,超过100万元的部分按1%提成,从键盘输入当月利润I,求应发放奖金总数?
程序分析 分区间计算即可。
profit=int(input('Show me the money: '))
bonus=0
thresholds=[100000,100000,200000,200000,400000]
rates=[0.1,0.075,0.05,0.03,0.015,0.01]
for i in range(len(thresholds)):
if profit<=thresholds[i]:
bonus+=profit*rates[i]
profit=0
break
else:
bonus+=thresholds[i]*rates[i]
profit-=thresholds[i]
bonus+=profit*rates[-1]
print(bonus)
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实例003:完全平方数
题目 一个整数,它加上100后是一个完全平方数,再加上168又是一个完全平方数,请问该数是多少?
程序分析 因为168对于指数爆炸来说实在太小了,所以可以直接省略数学分析,用最朴素的方法来获取上限:
n=0
while (n+1)**2-n*n<=168:
n+=1
print(n+1)
––––––––––
85
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思路是:最坏的结果是n的平方与(n+1)的平方刚好差168,由于是平方的关系,不可能存在比这更大的间隙。
至于判断是否是完全平方数,最简单的方法是:平方根的值小数为0即可。
结合起来:
n=0
while (n+1)**2-n*n<=168:
n+=1
for i in range((n+1)2):
if i0.5int(i0.5) and (i+168)0.5int((i+168)**0.5):
print(i–100)
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实例004:这天第几天
题目 输入某年某月某日,判断这一天是这一年的第几天?
程序分析 特殊情况,闰年时需考虑二月多加一天:
def isLeapYear(y):
return (y%400==0 or (y%4==0 and y%100!=0))
DofM=[0,31,28,31,30,31,30,31,31,30,31,30]
res=0
year=int(input('Year:'))
month=int(input('Month:'))
day=int(input('day:'))
if isLeapYear(year):
DofM[2]+=1
for i in range(month):
res+=DofM[i]
print(res+day)
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实例005:三数排序
题目 输入三个整数x,y,z,请把这三个数由小到大输出。
程序分析 练练手就随便找个排序算法实现一下,偷懒就直接调函数。
raw=[]
for i in range(3):
x=int(input('int%d: '%(i)))
raw.append(x)
for i in range(len(raw)):
for j in range(i,len(raw)):
if raw[i]>raw[j]:
raw[i],raw[j]=raw[j],raw[i]
print(raw)
raw2=[]
for i in range(3):
x=int(input(‘int%d: ‘%(i)))
raw2.append(x)
print(sorted(raw2))
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实例006:斐波那契数列
题目 斐波那契数列。
程序分析 斐波那契数列(Fibonacci sequence),从1,1开始,后面每一项等于前面两项之和。图方便就递归实现,图性能就用循环。
# 递归实现
def Fib(n):
return 1 if n<=2 else Fib(n-1)+Fib(n-2)
print(Fib(int(input())))
# 朴素实现
target=int(input())
res=0
a,b=1,1
for i in range(target–1):
a,b=b,a+b
print(a)
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实例007:copy
题目 将一个列表的数据复制到另一个列表中。
程序分析 使用列表[:],拿不准可以调用copy模块。
import copy
a = [1,2,3,4,['a','b']]
b = a # 赋值
c = a[:] # 浅拷贝
d = copy.copy(a) # 浅拷贝
e = copy.deepcopy(a) # 深拷贝
a.append(5)
a[4].append(‘c’)
print(‘a=’,a)
print(‘b=’,b)
print(‘c=’,c)
print(‘d=’,d)
print(‘e=’,e)
RESTART: F:\PyWorkspace\Python100\100examples<span class=“token number”>007.py
a= [1, 2, 3, 4, [‘a’, ‘b’, ‘c’], 5]
b= [1, 2, 3, 4, [‘a’, ‘b’, ‘c’], 5]
c= [1, 2, 3, 4, [‘a’, ‘b’, ‘c’]]
d= [1, 2, 3, 4, [‘a’, ‘b’, ‘c’]]
e= [1, 2, 3, 4, [‘a’, ‘b’]]
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实例008:九九乘法表
题目 输出 9*9 乘法口诀表。
程序分析 分行与列考虑,共9行9列,i控制行,j控制列。
for i in range(1,10):
for j in range(1,i+1):
print('%d*%d=%2ld '%(i,j,i*j),end='')
print()
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实例009:暂停一秒输出
题目 暂停一秒输出。
程序分析 使用 time 模块的 sleep() 函数。
import time
for i in range(4):
print(str(int(time.time()))[-2:])
time.sleep(1)
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实例010:给人看的时间
题目 暂停一秒输出,并格式化当前时间。
程序分析 同009.
import time
for i in range(4):
print(time.strftime(’%Y-%m-%d %H:%M:%S’,time.localtime(time.time())))
time.sleep(1)
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实例011:养兔子
题目 有一对兔子,从出生后第3个月起每个月都生一对兔子,小兔子长到第三个月后每个月又生一对兔子,假如兔子都不死,问每个月的兔子总数为多少?
程序分析 我认为原文的解法有点扯,没有考虑3个月成熟的问题,人家还是婴儿怎么生孩子?考虑到三个月成熟,可以构建四个数据,其中:一月兔每个月长大成为二月兔,二月兔变三月兔,三月兔变成年兔,成年兔(包括新成熟的三月兔)生等量的一月兔。
month=int(input('繁殖几个月?: '))
month_1=1
month_2=0
month_3=0
month_elder=0
for i in range(month):
month_1,month_2,month_3,month_elder=month_elder+month_3,month_1,month_2,month_elder+month_3
print('第%d个月共'%(i+1),month_1+month_2+month_3+month_elder,'对兔子')
print('其中1月兔:',month_1)
print('其中2月兔:',month_2)
print('其中3月兔:',month_3)
print('其中成年兔:',month_elder)
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实例012:100到200的素数
题目 判断101-200之间有多少个素数,并输出所有素数。
程序分析 判断素数的方法:用一个数分别去除2到sqrt(这个数),如果能被整除,则表明此数不是素数,反之是素数。 用else可以进一步简化代码.
import math
for i in range(100,200):
flag=0
for j in range(2,round(math.sqrt(i))+1):
if i%j==0:
flag=1
break
if flag:
continue
print(i)
print(’\nSimplify the code with “else”\n’)
for i in range(100,200):
for j in range(2,round(math.sqrt(i))+1):
if i%j==0:
break
else:
print(i)
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实例013:所有水仙花数
题目 打印出所有的”水仙花数”,所谓”水仙花数”是指一个三位数,其各位数字立方和等于该数本身。例如:153是一个”水仙花数”,因为153=1的三次方+5的三次方+3的三次方。
程序分析 利用for循环控制100-999个数,每个数分解出个位,十位,百位。
for i in range(100,1000):
s=str(i)
one=int(s[-1])
ten=int(s[-2])
hun=int(s[-3])
if i == one**3+ten**3+hun**3:
print(i)
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实例014:分解质因数
题目 将一个整数分解质因数。例如:输入90,打印出90=233*5。
程序分析 根本不需要判断是否是质数,从2开始向数本身遍历,能整除的肯定是最小的质数。
target=int(input('输入一个整数:'))
print(target,'= ',end='')
if target<0:
target=abs(target)
print(’-1*’,end=’’)
flag=0
if target<=1:
print(target)
flag=1
while True:
if flag:
break
for i in range(2,int(target+1)):
if target%i0:
print(“%d”%i,end=’’)
if targeti:
flag=1
break
print(’*’,end=’’)
target/=i
break
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实例015:分数归档
题目 利用条件运算符的嵌套来完成此题:学习成绩>=90分的同学用A表示,60-89分之间的用B表示,60分以下的用C表示。
程序分析 用条件判断即可。
points=int(input('输入分数:'))
if points>=90:
grade='A'
elif points<60:
grade='C'
else:
grade='B'
print(grade)
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实例016:输出日期
题目 输出指定格式的日期。
程序分析 使用 datetime 模块。
import datetime
print(datetime.date.today())
print(datetime.date(2333,2,3))
print(datetime.date.today().strftime('%d/%m/%Y'))
day=datetime.date(1111,2,3)
day=day.replace(year=day.year+22)
print(day)
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实例017:字符串构成
题目 输入一行字符,分别统计出其中英文字母、空格、数字和其它字符的个数。
程序分析 利用 while 或 for 语句,条件为输入的字符不为 ‘\n’。
string=input("输入字符串:")
alp=0
num=0
spa=0
oth=0
for i in range(len(string)):
if string[i].isspace():
spa+=1
elif string[i].isdigit():
num+=1
elif string[i].isalpha():
alp+=1
else:
oth+=1
print('space: ',spa)
print('digit: ',num)
print('alpha: ',alp)
print('other: ',oth)
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实例018:复读机相加
题目 求s=a+aa+aaa+aaaa+aa…a的值,其中a是一个数字。例如2+22+222+2222+22222(此时共有5个数相加),几个数相加由键盘控制。
程序分析 用字符串解决。
a=input('被加数字:')
n=int(input('加几次?:'))
res=0
for i in range(n):
res+=int(a)
a+=a[0]
print('结果是:',res)
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实例019:完数
题目 一个数如果恰好等于它的因子之和,这个数就称为”完数”。例如6=1+2+3.编程找出1000以内的所有完数。
程序分析 将每一对因子加进集合,在这个过程中已经自动去重。最后的结果要求不计算其本身。
def factor(num):
target=int(num)
res=set()
for i in range(1,num):
if num%i==0:
res.add(i)
res.add(num/i)
return res
for i in range(2,1001):
if i==sum(factor(i))–i:
print(i)
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实例020:高空抛物
题目 一球从100米高度自由落下,每次落地后反跳回原高度的一半;再落下,求它在第10次落地时,共经过多少米?第10次反弹多高?
程序分析 无
high=200.
total=100
for i in range(10):
high/=2
total+=high
print(high/2)
print('总长:',total)
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实例021:猴子偷桃
题目 猴子吃桃问题:猴子第一天摘下若干个桃子,当即吃了一半,还不瘾,又多吃了一个第二天早上又将剩下的桃子吃掉一半,又多吃了一个。以后每天早上都吃了前一天剩下的一半零一个。到第10天早上想再吃时,见只剩下一个桃子了。求第一天共摘了多少。
程序分析 按规则反向推断:猴子有一个桃子,他偷来一个桃子,觉得不够又偷来了与手上等量的桃子,一共偷了9天。
peach=1
for i in range(9):
peach=(peach+1)*2
print(peach)
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实例022:比赛对手
题目 两个乒乓球队进行比赛,各出三人。甲队为a,b,c三人,乙队为x,y,z三人。已抽签决定比赛名单。有人向队员打听比赛的名单。a说他不和x比,c说他不和x,z比,请编程序找出三队赛手的名单。
程序分析 找到条件下不重复的三个对手即可。
a=set(['x','y','z'])
b=set(['x','y','z'])
c=set(['x','y','z'])
c-=set(('x','z'))
a-=set('x')
for i in a:
for j in b:
for k in c:
if len(set((i,j,k)))==3:
print('a:%s,b:%s,c:%s'%(i,j,k))
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实例023:画菱形
题目 打印出如下图案(菱形):
*
***
*****
*******
*****
***
*
程序分析 递归调用即可。
def draw(num):
a="*"*(2*(4-num)+1)
print(a.center(9,' '))
if num!=1:
draw(num-1)
print(a.center(9,' '))
draw(4)
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实例024:斐波那契数列II
题目 有一分数序列:2/1,3/2,5/3,8/5,13/8,21/13…求出这个数列的前20项之和。
程序分析 就是斐波那契数列的后一项除以前一项。
a = 2.0
b = 1.0
s = 0
for n in range(1,21):
s += a / b
a,b = a + b,a
print (s)
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实例025: 阶乘求和
题目 求1+2!+3!+…+20!的和。
程序分析 1+2!+3!+…+20!=1+2(1+3(1+4(…20(1))))
res=1
for i in range(20,1,-1):
res=i*res+1
print(res)
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实例026:递归求阶乘
题目 利用递归方法求5!。
程序分析 递归调用即可。
def factorial(n):
return n*factorial(n-1) if n>1 else 1
print(factorial(5))
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实例027:递归输出
题目 利用递归函数调用方式,将所输入的5个字符,以相反顺序打印出来。
程序分析 递归真是蠢方法。
def rec(string):
if len(string)!=1:
rec(string[1:])
print(string[0],end='')
rec(input(‘string here:’))
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实例028:递归求等差数列
题目 有5个人坐在一起,问第五个人多少岁?他说比第4个人大2岁。问第4个人岁数,他说比第3个人大2岁。问第三个人,又说比第2人大两岁。问第2个人,说比第一个人大两岁。最后问第一个人,他说是10岁。请问第五个人多大?
程序分析 就一等差数列。
def age(n):
if n==1:
return 10
return 2+age(n-1)
print(age(5))
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实例029:反向输出
题目 给一个不多于5位的正整数,要求:一、求它是几位数,二、逆序打印出各位数字。
程序分析 学会分解出每一位数,用字符串的方法总是比较省事。
n=int(input('输入一个正整数:'))
n=str(n)
print('%d位数'%len(n))
print(n[::-1])
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实例030:回文数
题目 一个5位数,判断它是不是回文数。即12321是回文数,个位与万位相同,十位与千位相同。
程序分析 用字符串比较方便,就算输入的不是数字都ok。
n=input("随便你输入啥啦:")
a=0
b=len(n)-1
flag=True
while a<b:
if n[a]!=n[b]:
print('不是回文串')
flag=False
break
a,b=a+1,b-1
if flag:
print('是回文串')
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实例031:字母识词
题目 请输入星期几的第一个字母来判断一下是星期几,如果第一个字母一样,则继续判断第二个字母。
程序分析 这里用字典的形式直接将对照关系存好。
weekT={'h':'thursday',
'u':'tuesday'}
weekS={'a':'saturday',
'u':'sunday'}
week={'t':weekT,
's':weekS,
'm':'monday',
'w':'wensday',
'f':'friday'}
a=week[str(input('请输入第一位字母:')).lower()]
if a==weekT or a==weekS:
print(a[str(input('请输入第二位字母:')).lower()])
else:
print(a)
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实例032:反向输出II
题目 按相反的顺序输出列表的值。
程序分析 无。
a = ['one', 'two', 'three']
print(a[::-1])
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实例033:列表转字符串
题目 按逗号分隔列表。
程序分析 无。
L = [1,2,3,4,5]
print(','.join(str(n) for n in L))
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实例034:调用函数
题目 练习函数调用。
程序分析 无。
def hello():
print('Hello World!')
def helloAgain():
for i in range(2):
hello()
if name==‘main’:
helloAgain()
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实例035:设置输出颜色
题目 文本颜色设置。
程序分析 无。
class bcolors:
HEADER = '\033[95m'
OKBLUE = '\033[94m'
OKGREEN = '\033[92m'
WARNING = '\033[93m'
FAIL = '\033[91m'
ENDC = '\033[0m'
BOLD = '\033[1m'
UNDERLINE = '\033[4m'
print(bcolors.WARNING + "警告的颜色字体?" + bcolors.ENDC)
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实例036:算素数
题目 求100之内的素数。
程序分析 用else执行for循环的奖励代码(如果for是正常完结,非break)。
lo=int(input('下限:'))
hi=int(input('上限:'))
for i in range(lo,hi+1):
if i > 1:
for j in range(2,i):
if (i % j) == 0:
break
else:
print(i)
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实例037:排序
题目 对10个数进行排序。
程序分析 同实例005。
raw=[]
for i in range(10):
x=int(input('int%d: '%(i)))
raw.append(x)
for i in range(len(raw)):
for j in range(i,len(raw)):
if raw[i]>raw[j]:
raw[i],raw[j]=raw[j],raw[i]
print(raw)
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实例038:矩阵对角线之和
题目 求一个3*3矩阵主对角线元素之和。
程序分析 无。
mat=[[1,2,3],
[3,4,5],
[4,5,6]
]
res=0
for i in range(len(mat)):
res+=mat[i][i]
print(res)
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实例039:有序列表插入元素
题目 有一个已经排好序的数组。现输入一个数,要求按原来的规律将它插入数组中。
程序分析 首先判断此数是否大于最后一个数,然后再考虑插入中间的数的情况,插入后此元素之后的数,依次后移一个位置。
lis=[1,10,100,1000,10000,100000]
n=int(input('insert a number: '))
lis.append(n)
for i in range(len(lis)-1):
if lis[i]>=n:
for j in range(i,len(lis)):
lis[j],lis[-1]=lis[-1],lis[j]
break
print(lis)
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实例040:逆序列表
题目 将一个数组逆序输出。
程序分析 依次交换位置,或者直接调用reverse方法。
lis=[1,10,100,1000,10000,100000]
for i in range(int(len(lis)/2)):
lis[i],lis[len(lis)-1-i]=lis[len(lis)-1-i],lis[i]
print('第一种实现:')
print(lis)
lis=[1,10,100,1000,10000,100000]
print(‘第二种实现:’)
lis.reverse()
print(lis)
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实例041:类的方法与变量
题目 模仿静态变量的用法。
程序分析 构造类,了解类的方法与变量。
def dummy():
i=0
print(i)
i+=1
class cls:
i=0
def dummy(self):
print(self.i)
self.i+=1
a=cls()
for i in range(50):
dummy()
a.dummy()
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实例042:变量作用域
题目 学习使用auto定义变量的用法。
程序分析 python中的变量作用域。
i=0
n=0
def dummy():
i=0
print(i)
i+=1
def dummy2():
global n
print(n)
n+=1
print('函数内部的同名变量')
for j in range(20):
print(i)
dummy()
i+=1
print('global声明同名变量')
for k in range(20):
print(n)
dummy2()
n+=10
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实例043:作用域、类的方法与变量
题目 模仿静态变量(static)另一案例。
程序分析 综合实例041和实例042。
class dummy:
num=1
def Num(self):
print('class dummy num:',self.num)
print('global num: ',num)
self.num+=1
n=dummy()
num=1
for i in range(5):
num*=10
n.Num()
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实例044:矩阵相加
题目 计算两个矩阵相加。
程序分析 创建一个新的矩阵,使用 for 迭代并取出 X 和 Y 矩阵中对应位置的值,相加后放到新矩阵的对应位置中。
X = [[12,7,3],
[4 ,5,6],
[7 ,8,9]]
Y = [[5,8,1],
[6,7,3],
[4,5,9]]
res=[[0,0,0],
[0,0,0],
[0,0,0]]
for i in range(len(res)):
for j in range(len(res[0])):
res[i][j]=X[i][j]+Y[i][j]
print(res)
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实例045:求和
题目 统计 1 到 100 之和。
程序分析 无
res=0
for i in range(1,101):
res+=i
print(res)
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实例046:打破循环
题目 求输入数字的平方,如果平方运算后小于 50 则退出。
程序分析 无
while True:
try:
n=float(input('输入一个数字:'))
except:
print('输入错误')
continue
dn=n**2
print('其平方为:',dn)
if dn<50:
print('平方小于50,退出')
break
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实例047:函数交换变量
题目 两个变量值用函数互换。
程序分析 无
def exc(a,b):
return (b,a)
a=0
b=10
a,b=exc(a,b)
print(a,b)
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实例048:数字比大小
题目 数字比较。
程序分析 无
a=int(input('a='))
b=int(input('b='))
if a<b:
print('a<b')
elif a>b:
print('a>b')
else:
print('a=b')
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实例049:lambda
题目 使用lambda来创建匿名函数。
程序分析 无
Max=lambda x,y:x*(x>=y)+y*(y>x)
Min=lambda x,y:x*(x<=y)+y*(y<x)
a=int(input(‘1:’))
b=int(input(‘2:’))
print(Max(a,b))
print(Min(a,b))
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实例050:随机数
题目 输出一个随机数。
程序分析 使用 random 模块。
import random
print(random.uniform(10,20))
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实例051:按位与
题目 学习使用按位与 & 。
程序分析 0&0=0; 0&1=0; 1&0=0; 1&1=1。
a=0o77
print(a)
b=a&3
print(b)
b=b&7
print(b)
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实例052:按位或
题目 学习使用按位或 | 。
程序分析 0|0=0; 0|1=1; 1|0=1; 1|1=1
a=0o77
print(a|3)
print(a|3|7)
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实例053:按位异或
题目 学习使用按位异或 ^ 。
程序分析 0^0=0; 0^1=1; 1^0=1; 1^1=0
a=0o77
print(a^3)
print(a^3^7)
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实例054:位取反、位移动
题目 取一个整数a从右端开始的4〜7位。
程序分析 可以这样考虑:
(1)先使a右移4位。
(2)设置一个低4位全为1,其余全为0的数。可用(0<<4)
(3)将上面二者进行&运算。
a=int(input('输入一个数字: '))
b=0 # 0
b=~b # 1
b=b<<4 # 10000
b=~b # 1111
c=a>>4
d=c&b
print('a:',bin(a))
print('b:',bin(b))
print('c:',bin(c))
print('d:',bin(d))
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实例055:按位取反
题目 学习使用按位取反~。
程序分析 ~0=1; ~1=0;
print(~234)
print(~~234)
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实例056:画圈
题目 画图,学用circle画圆形。
程序分析 无。
from tkinter import *
canvas=Canvas(width=800,height=600,bg='yellow')
canvas.pack(expand=YES,fill=BOTH)
k=1
j=1
for i in range(26):
canvas.create_oval(310-k,250-k,310+k,250+k,width=1)
k+=j
j+=0.3
mainloop()
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实例057:画线
题目 画图,学用line画直线。
程序分析 无。
if __name__ == '__main__': from tkinter import *
canvas <span class="token operator">=</span> Canvas<span class="token punctuation">(</span>width<span class="token operator">=</span><span class="token number">300</span><span class="token punctuation">,</span> height<span class="token operator">=</span><span class="token number">300</span><span class="token punctuation">,</span> bg<span class="token operator">=</span><span class="token string">'green'</span><span class="token punctuation">)</span> canvas<span class="token punctuation">.</span>pack<span class="token punctuation">(</span>expand<span class="token operator">=</span>YES<span class="token punctuation">,</span> fill<span class="token operator">=</span>BOTH<span class="token punctuation">)</span> x0 <span class="token operator">=</span> <span class="token number">263</span> y0 <span class="token operator">=</span> <span class="token number">263</span> y1 <span class="token operator">=</span> <span class="token number">275</span> x1 <span class="token operator">=</span> <span class="token number">275</span> <span class="token keyword">for</span> i <span class="token keyword">in</span> <span class="token builtin">range</span><span class="token punctuation">(</span><span class="token number">19</span><span class="token punctuation">)</span><span class="token punctuation">:</span> canvas<span class="token punctuation">.</span>create_line<span class="token punctuation">(</span>x0<span class="token punctuation">,</span>y0<span class="token punctuation">,</span>x0<span class="token punctuation">,</span>y1<span class="token punctuation">,</span> width<span class="token operator">=</span><span class="token number">1</span><span class="token punctuation">,</span> fill<span class="token operator">=</span><span class="token string">'red'</span><span class="token punctuation">)</span> x0 <span class="token operator">=</span> x0 <span class="token operator">-</span> <span class="token number">5</span> y0 <span class="token operator">=</span> y0 <span class="token operator">-</span> <span class="token number">5</span> x1 <span class="token operator">=</span> x1 <span class="token operator">+</span> <span class="token number">5</span> y1 <span class="token operator">=</span> y1 <span class="token operator">+</span> <span class="token number">5</span> x0 <span class="token operator">=</span> <span class="token number">263</span> y1 <span class="token operator">=</span> <span class="token number">275</span> y0 <span class="token operator">=</span> <span class="token number">263</span> <span class="token keyword">for</span> i <span class="token keyword">in</span> <span class="token builtin">range</span><span class="token punctuation">(</span><span class="token number">21</span><span class="token punctuation">)</span><span class="token punctuation">:</span> canvas<span class="token punctuation">.</span>create_line<span class="token punctuation">(</span>x0<span class="token punctuation">,</span>y0<span class="token punctuation">,</span>x0<span class="token punctuation">,</span>y1<span class="token punctuation">,</span>fill <span class="token operator">=</span> <span class="token string">'red'</span><span class="token punctuation">)</span> x0 <span class="token operator">+=</span> <span class="token number">5</span> y0 <span class="token operator">+=</span> <span class="token number">5</span> y1 <span class="token operator">+=</span> <span class="token number">5</span> mainloop<span class="token punctuation">(</span><span class="token punctuation">)</span>
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实例058:画矩形
题目 画图,学用rectangle画方形。
程序分析 无。
if __name__ == '__main__': from tkinter import * root = Tk() root.title('Canvas') canvas = Canvas(root,width = 400,height = 400,bg = 'yellow') x0 = 263 y0 = 263 y1 = 275 x1 = 275 for i in range(19): canvas.create_rectangle(x0,y0,x1,y1) x0 -= 5 y0 -= 5 x1 += 5 y1 += 5
canvas<span class="token punctuation">.</span>pack<span class="token punctuation">(</span><span class="token punctuation">)</span> root<span class="token punctuation">.</span>mainloop<span class="token punctuation">(</span><span class="token punctuation">)</span>
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实例059:画图(丑)
题目 画图,综合例子。
程序分析 丑。
if __name__ == '__main__': from tkinter import * canvas = Canvas(width = 300,height = 300,bg = 'green') canvas.pack(expand = YES,fill = BOTH) x0 = 150 y0 = 100 canvas.create_oval(x0 - 10,y0 - 10,x0 + 10,y0 + 10) canvas.create_oval(x0 - 20,y0 - 20,x0 + 20,y0 + 20) canvas.create_oval(x0 - 50,y0 - 50,x0 + 50,y0 + 50) import math B = 0.809 for i in range(16): a = 2 * math.pi / 16 * i x = math.ceil(x0 + 48 * math.cos(a)) y = math.ceil(y0 + 48 * math.sin(a) * B) canvas.create_line(x0,y0,x,y,fill = 'red') canvas.create_oval(x0 - 60,y0 - 60,x0 + 60,y0 + 60)
<span class="token keyword">for</span> k <span class="token keyword">in</span> <span class="token builtin">range</span><span class="token punctuation">(</span><span class="token number">501</span><span class="token punctuation">)</span><span class="token punctuation">:</span> <span class="token keyword">for</span> i <span class="token keyword">in</span> <span class="token builtin">range</span><span class="token punctuation">(</span><span class="token number">17</span><span class="token punctuation">)</span><span class="token punctuation">:</span> a <span class="token operator">=</span> <span class="token punctuation">(</span><span class="token number">2</span> <span class="token operator">*</span> math<span class="token punctuation">.</span>pi <span class="token operator">/</span> <span class="token number">16</span><span class="token punctuation">)</span> <span class="token operator">*</span> i <span class="token operator">+</span> <span class="token punctuation">(</span><span class="token number">2</span> <span class="token operator">*</span> math<span class="token punctuation">.</span>pi <span class="token operator">/</span> <span class="token number">180</span><span class="token punctuation">)</span> <span class="token operator">*</span> k x <span class="token operator">=</span> math<span class="token punctuation">.</span>ceil<span class="token punctuation">(</span>x0 <span class="token operator">+</span> <span class="token number">48</span> <span class="token operator">*</span> math<span class="token punctuation">.</span>cos<span class="token punctuation">(</span>a<span class="token punctuation">)</span><span class="token punctuation">)</span> y <span class="token operator">=</span> math<span class="token punctuation">.</span>ceil<span class="token punctuation">(</span>y0 <span class="token operator">+</span> <span class="token number">48</span> <span class="token operator">+</span> math<span class="token punctuation">.</span>sin<span class="token punctuation">(</span>a<span class="token punctuation">)</span> <span class="token operator">*</span> B<span class="token punctuation">)</span> canvas<span class="token punctuation">.</span>create_line<span class="token punctuation">(</span>x0<span class="token punctuation">,</span>y0<span class="token punctuation">,</span>x<span class="token punctuation">,</span>y<span class="token punctuation">,</span>fill <span class="token operator">=</span> <span class="token string">'red'</span><span class="token punctuation">)</span> <span class="token keyword">for</span> j <span class="token keyword">in</span> <span class="token builtin">range</span><span class="token punctuation">(</span><span class="token number">51</span><span class="token punctuation">)</span><span class="token punctuation">:</span> a <span class="token operator">=</span> <span class="token punctuation">(</span><span class="token number">2</span> <span class="token operator">*</span> math<span class="token punctuation">.</span>pi <span class="token operator">/</span> <span class="token number">16</span><span class="token punctuation">)</span> <span class="token operator">*</span> i <span class="token operator">+</span> <span class="token punctuation">(</span><span class="token number">2</span><span class="token operator">*</span> math<span class="token punctuation">.</span>pi <span class="token operator">/</span> <span class="token number">180</span><span class="token punctuation">)</span> <span class="token operator">*</span> k <span class="token operator">-</span> <span class="token number">1</span> x <span class="token operator">=</span> math<span class="token punctuation">.</span>ceil<span class="token punctuation">(</span>x0 <span class="token operator">+</span> <span class="token number">48</span> <span class="token operator">*</span> math<span class="token punctuation">.</span>cos<span class="token punctuation">(</span>a<span class="token punctuation">)</span><span class="token punctuation">)</span> y <span class="token operator">=</span> math<span class="token punctuation">.</span>ceil<span class="token punctuation">(</span>y0 <span class="token operator">+</span> <span class="token number">48</span> <span class="token operator">*</span> math<span class="token punctuation">.</span>sin<span class="token punctuation">(</span>a<span class="token punctuation">)</span> <span class="token operator">*</span> B<span class="token punctuation">)</span> canvas<span class="token punctuation">.</span>create_line<span class="token punctuation">(</span>x0<span class="token punctuation">,</span>y0<span class="token punctuation">,</span>x<span class="token punctuation">,</span>y<span class="token punctuation">,</span>fill <span class="token operator">=</span> <span class="token string">'red'</span><span class="token punctuation">)</span> mainloop<span class="token punctuation">(</span><span class="token punctuation">)</span>
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实例060:字符串长度
题目 计算字符串长度。
程序分析 无。
s='zhangguang101'
print(len(s))
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实例061:杨辉三角
题目 打印出杨辉三角形前十行。
程序分析 无。
def generate(numRows):
r = [[1]]
for i in range(1,numRows):
r.append(list(map(lambda x,y:x+y, [0]+r[-1],r[-1]+[0])))
return r[:numRows]
a=generate(10)
for i in a:
print(i)
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实例062:查找字符串
题目 查找字符串。
程序分析 无。
s1='aabbxuebixuebi'
s2='ab'
s3='xue'
print(s1.find(s2))
print(s1.find(s3))
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实例063:画椭圆
题目 画椭圆。
程序分析 使用 tkinter。
if __name__ == '__main__': from tkinter import * x = 360 y = 160 top = y - 30 bottom = y - 30
canvas <span class="token operator">=</span> Canvas<span class="token punctuation">(</span>width <span class="token operator">=</span> <span class="token number">400</span><span class="token punctuation">,</span>height <span class="token operator">=</span> <span class="token number">600</span><span class="token punctuation">,</span>bg <span class="token operator">=</span> <span class="token string">'white'</span><span class="token punctuation">)</span> <span class="token keyword">for</span> i <span class="token keyword">in</span> <span class="token builtin">range</span><span class="token punctuation">(</span><span class="token number">20</span><span class="token punctuation">)</span><span class="token punctuation">:</span> canvas<span class="token punctuation">.</span>create_oval<span class="token punctuation">(</span><span class="token number">250</span> <span class="token operator">-</span> top<span class="token punctuation">,</span><span class="token number">250</span> <span class="token operator">-</span> bottom<span class="token punctuation">,</span><span class="token number">250</span> <span class="token operator">+</span> top<span class="token punctuation">,</span><span class="token number">250</span> <span class="token operator">+</span> bottom<span class="token punctuation">)</span> top <span class="token operator">-=</span> <span class="token number">5</span> bottom <span class="token operator">+=</span> <span class="token number">5</span> canvas<span class="token punctuation">.</span>pack<span class="token punctuation">(</span><span class="token punctuation">)</span> mainloop<span class="token punctuation">(</span><span class="token punctuation">)</span>
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实例064:画椭圆、矩形
题目 利用ellipse 和 rectangle 画图。。
程序分析 无。
if __name__ == '__main__': from tkinter import * canvas = Canvas(width = 400,height = 600,bg = 'white') left = 20 right = 50 top = 50 num = 15 for i in range(num): canvas.create_oval(250 - right,250 - left,250 + right,250 + left) canvas.create_oval(250 - 20,250 - top,250 + 20,250 + top) canvas.create_rectangle(20 - 2 * i,20 - 2 * i,10 * (i + 2),10 * ( i + 2)) right += 5 left += 5 top += 10
canvas<span class="token punctuation">.</span>pack<span class="token punctuation">(</span><span class="token punctuation">)</span> mainloop<span class="token punctuation">(</span><span class="token punctuation">)</span>
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实例065:画组合图形
题目 一个最优美的图案。
程序分析 无。
import math
from tkinter import *
class PTS:
def init(self):
self.x = 0
self.y = 0
points = []
def LineToDemo():
screenx = 400
screeny = 400
canvas = Canvas(width = screenx,height = screeny,bg = ‘white’)
AspectRatio <span class="token operator">=</span> <span class="token number">0.85</span>
MAXPTS <span class="token operator">=</span> <span class="token number">15</span>
h <span class="token operator">=</span> screeny
w <span class="token operator">=</span> screenx
xcenter <span class="token operator">=</span> w <span class="token operator">/</span> <span class="token number">2</span>
ycenter <span class="token operator">=</span> h <span class="token operator">/</span> <span class="token number">2</span>
radius <span class="token operator">=</span> <span class="token punctuation">(</span>h <span class="token operator">-</span> <span class="token number">30</span><span class="token punctuation">)</span> <span class="token operator">/</span> <span class="token punctuation">(</span>AspectRatio <span class="token operator">*</span> <span class="token number">2</span><span class="token punctuation">)</span> <span class="token operator">-</span> <span class="token number">20</span>
step <span class="token operator">=</span> <span class="token number">360</span> <span class="token operator">/</span> MAXPTS
angle <span class="token operator">=</span> <span class="token number">0.0</span>
<span class="token keyword">for</span> i <span class="token keyword">in</span> <span class="token builtin">range</span><span class="token punctuation">(</span>MAXPTS<span class="token punctuation">)</span><span class="token punctuation">:</span>
rads <span class="token operator">=</span> angle <span class="token operator">*</span> math<span class="token punctuation">.</span>pi <span class="token operator">/</span> <span class="token number">180.0</span>
p <span class="token operator">=</span> PTS<span class="token punctuation">(</span><span class="token punctuation">)</span>
p<span class="token punctuation">.</span>x <span class="token operator">=</span> xcenter <span class="token operator">+</span> <span class="token builtin">int</span><span class="token punctuation">(</span>math<span class="token punctuation">.</span>cos<span class="token punctuation">(</span>rads<span class="token punctuation">)</span> <span class="token operator">*</span> radius<span class="token punctuation">)</span>
p<span class="token punctuation">.</span>y <span class="token operator">=</span> ycenter <span class="token operator">-</span> <span class="token builtin">int</span><span class="token punctuation">(</span>math<span class="token punctuation">.</span>sin<span class="token punctuation">(</span>rads<span class="token punctuation">)</span> <span class="token operator">*</span> radius <span class="token operator">*</span> AspectRatio<span class="token punctuation">)</span>
angle <span class="token operator">+=</span> step
points<span class="token punctuation">.</span>append<span class="token punctuation">(</span>p<span class="token punctuation">)</span>
canvas<span class="token punctuation">.</span>create_oval<span class="token punctuation">(</span>xcenter <span class="token operator">-</span> radius<span class="token punctuation">,</span>ycenter <span class="token operator">-</span> radius<span class="token punctuation">,</span>
xcenter <span class="token operator">+</span> radius<span class="token punctuation">,</span>ycenter <span class="token operator">+</span> radius<span class="token punctuation">)</span>
<span class="token keyword">for</span> i <span class="token keyword">in</span> <span class="token builtin">range</span><span class="token punctuation">(</span>MAXPTS<span class="token punctuation">)</span><span class="token punctuation">:</span>
<span class="token keyword">for</span> j <span class="token keyword">in</span> <span class="token builtin">range</span><span class="token punctuation">(</span>i<span class="token punctuation">,</span>MAXPTS<span class="token punctuation">)</span><span class="token punctuation">:</span>
canvas<span class="token punctuation">.</span>create_line<span class="token punctuation">(</span>points<span class="token punctuation">[</span>i<span class="token punctuation">]</span><span class="token punctuation">.</span>x<span class="token punctuation">,</span>points<span class="token punctuation">[</span>i<span class="token punctuation">]</span><span class="token punctuation">.</span>y<span class="token punctuation">,</span>points<span class="token punctuation">[</span>j<span class="token punctuation">]</span><span class="token punctuation">.</span>x<span class="token punctuation">,</span>points<span class="token punctuation">[</span>j<span class="token punctuation">]</span><span class="token punctuation">.</span>y<span class="token punctuation">)</span>
canvas<span class="token punctuation">.</span>pack<span class="token punctuation">(</span><span class="token punctuation">)</span>
mainloop<span class="token punctuation">(</span><span class="token punctuation">)</span>
if name == ‘main’:
LineToDemo()
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实例066:三数排序
题目 输入3个数a,b,c,按大小顺序输出。
程序分析 同实例005。
raw=[]
for i in range(3):
x=int(input('int%d: '%(i)))
raw.append(x)
for i in range(len(raw)):
for j in range(i,len(raw)):
if raw[i]>raw[j]:
raw[i],raw[j]=raw[j],raw[i]
print(raw)
raw2=[]
for i in range(3):
x=int(input('int%d: '%(i)))
raw2.append(x)
print(sorted(raw2))
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实例067:交换位置
题目 输入数组,最大的与第一个元素交换,最小的与最后一个元素交换,输出数组。
程序分析 无。
li=[3,2,5,7,8,1,5]
li[-1],li[li.index(min(li))]=li[li.index(min(li))],li[-1]
m=li[0]
ind=li.index(max(li))
li[0]=li[ind]
li[ind]=m
print(li)
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实例068:旋转数列
题目 有n个整数,使其前面各数顺序向后移m个位置,最后m个数变成最前面的m个数
程序分析 无。
from collections import *
li=[1,2,3,4,5,6,7,8,9]
deq=deque(li,maxlen=len(li))
print(li)
deq.rotate(int(input('rotate:')))
print(list(deq))
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实例069:报数
题目 有n个人围成一圈,顺序排号。从第一个人开始报数(从1到3报数),凡报到3的人退出圈子,问最后留下的是原来第几号的那位。
程序分析 无。
if __name__ == '__main__': nmax = 50 n = int(input('请输入总人数:')) num = [] for i in range(n): num.append(i + 1)
i <span class="token operator">=</span> <span class="token number">0</span> k <span class="token operator">=</span> <span class="token number">0</span> m <span class="token operator">=</span> <span class="token number">0</span> <span class="token keyword">while</span> m <span class="token operator"><</span> n <span class="token operator">-</span> <span class="token number">1</span><span class="token punctuation">:</span> <span class="token keyword">if</span> num<span class="token punctuation">[</span>i<span class="token punctuation">]</span> <span class="token operator">!=</span> <span class="token number">0</span> <span class="token punctuation">:</span> k <span class="token operator">+=</span> <span class="token number">1</span> <span class="token keyword">if</span> k <span class="token operator">==</span> <span class="token number">3</span><span class="token punctuation">:</span> num<span class="token punctuation">[</span>i<span class="token punctuation">]</span> <span class="token operator">=</span> <span class="token number">0</span> k <span class="token operator">=</span> <span class="token number">0</span> m <span class="token operator">+=</span> <span class="token number">1</span> i <span class="token operator">+=</span> <span class="token number">1</span> <span class="token keyword">if</span> i <span class="token operator">==</span> n <span class="token punctuation">:</span> i <span class="token operator">=</span> <span class="token number">0</span> i <span class="token operator">=</span> <span class="token number">0</span> <span class="token keyword">while</span> num<span class="token punctuation">[</span>i<span class="token punctuation">]</span> <span class="token operator">==</span> <span class="token number">0</span><span class="token punctuation">:</span> i <span class="token operator">+=</span> <span class="token number">1</span> <span class="token keyword">print</span><span class="token punctuation">(</span>num<span class="token punctuation">[</span>i<span class="token punctuation">]</span><span class="token punctuation">)</span>
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实例070:字符串长度II
题目 写一个函数,求一个字符串的长度,在main函数中输入字符串,并输出其长度。
程序分析 无。
def lenofstr(s):
return len(s)
print(lenofstr(‘tanxiaofengsheng’))
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实例071:输入和输出
题目 编写input()和output()函数输入,输出5个学生的数据记录。
程序分析 无。
N = 3
#stu
# num : string
# name : string
# score[4]: list
student = []
for i in range(5):
student.append(['','',[]])
def input_stu(stu):
for i in range(N):
stu[i][0] = input(‘input student num:\n’)
stu[i][1] = input(‘input student name:\n’)
for j in range(3):
stu[i][2].append(int(input(‘score:\n’)))
def output_stu(stu):
for i in range(N):
print (’%-6s%-10s’ % ( stu[i][0],stu[i][1] ))
for j in range(3):
print (’%-8d’ % stu[i][2][j])
if name == ‘main’:
input_stu(student)
print (student)
output_stu(student)
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实例072:创建链表
题目 创建一个链表。
程序分析 原文不太靠谱。
class Node:
<span class="token keyword">def</span> <span class="token function">__init__</span><span class="token punctuation">(</span>self<span class="token punctuation">,</span> data<span class="token punctuation">)</span><span class="token punctuation">:</span> self<span class="token punctuation">.</span>data <span class="token operator">=</span> data self<span class="token punctuation">.</span><span class="token builtin">next</span> <span class="token operator">=</span> <span class="token boolean">None</span> <span class="token keyword">def</span> <span class="token function">get_data</span><span class="token punctuation">(</span>self<span class="token punctuation">)</span><span class="token punctuation">:</span> <span class="token keyword">return</span> self<span class="token punctuation">.</span>data
class List:
<span class="token keyword">def</span> <span class="token function">__init__</span><span class="token punctuation">(</span>self<span class="token punctuation">,</span> head<span class="token punctuation">)</span><span class="token punctuation">:</span> self<span class="token punctuation">.</span>head <span class="token operator">=</span> head <span class="token keyword">def</span> <span class="token function">is_empty</span><span class="token punctuation">(</span>self<span class="token punctuation">)</span><span class="token punctuation">:</span> <span class="token keyword">return</span> self<span class="token punctuation">.</span>get_len<span class="token punctuation">(</span><span class="token punctuation">)</span> <span class="token operator">==</span> <span class="token number">0</span> <span class="token keyword">def</span> <span class="token function">get_len</span><span class="token punctuation">(</span>self<span class="token punctuation">)</span><span class="token punctuation">:</span> length <span class="token operator">=</span> <span class="token number">0</span> temp <span class="token operator">=</span> self<span class="token punctuation">.</span>head <span class="token keyword">while</span> temp <span class="token keyword">is</span> <span class="token operator">not</span> <span class="token boolean">None</span><span class="token punctuation">:</span> length <span class="token operator">+=</span> <span class="token number">1</span> temp <span class="token operator">=</span> temp<span class="token punctuation">.</span><span class="token builtin">next</span> <span class="token keyword">return</span> length <span class="token keyword">def</span> <span class="token function">append</span><span class="token punctuation">(</span>self<span class="token punctuation">,</span> node<span class="token punctuation">)</span><span class="token punctuation">:</span> temp <span class="token operator">=</span> self<span class="token punctuation">.</span>head <span class="token keyword">while</span> temp<span class="token punctuation">.</span><span class="token builtin">next</span> <span class="token keyword">is</span> <span class="token operator">not</span> <span class="token boolean">None</span><span class="token punctuation">:</span> temp <span class="token operator">=</span> temp<span class="token punctuation">.</span><span class="token builtin">next</span> temp<span class="token punctuation">.</span><span class="token builtin">next</span> <span class="token operator">=</span> node <span class="token keyword">def</span> <span class="token function">delete</span><span class="token punctuation">(</span>self<span class="token punctuation">,</span> index<span class="token punctuation">)</span><span class="token punctuation">:</span> <span class="token keyword">if</span> index <span class="token operator"><</span> <span class="token number">1</span> <span class="token operator">or</span> index <span class="token operator">></span> self<span class="token punctuation">.</span>get_len<span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">:</span> <span class="token keyword">print</span><span class="token punctuation">(</span><span class="token string">"给定位置不合理"</span><span class="token punctuation">)</span> <span class="token keyword">return</span> <span class="token keyword">if</span> index <span class="token operator">==</span> <span class="token number">1</span><span class="token punctuation">:</span> self<span class="token punctuation">.</span>head <span class="token operator">=</span> self<span class="token punctuation">.</span>head<span class="token punctuation">.</span><span class="token builtin">next</span> <span class="token keyword">return</span> temp <span class="token operator">=</span> self<span class="token punctuation">.</span>head cur_pos <span class="token operator">=</span> <span class="token number">0</span> <span class="token keyword">while</span> temp <span class="token keyword">is</span> <span class="token operator">not</span> <span class="token boolean">None</span><span class="token punctuation">:</span> cur_pos <span class="token operator">+=</span> <span class="token number">1</span> <span class="token keyword">if</span> cur_pos <span class="token operator">==</span> index<span class="token operator">-</span><span class="token number">1</span><span class="token punctuation">:</span> temp<span class="token punctuation">.</span><span class="token builtin">next</span> <span class="token operator">=</span> temp<span class="token punctuation">.</span><span class="token builtin">next</span><span class="token punctuation">.</span><span class="token builtin">next</span> temp <span class="token operator">=</span> temp<span class="token punctuation">.</span><span class="token builtin">next</span> <span class="token keyword">def</span> <span class="token function">insert</span><span class="token punctuation">(</span>self<span class="token punctuation">,</span> pos<span class="token punctuation">,</span> node<span class="token punctuation">)</span><span class="token punctuation">:</span> <span class="token keyword">if</span> pos <span class="token operator"><</span> <span class="token number">1</span> <span class="token operator">or</span> pos <span class="token operator">></span> self<span class="token punctuation">.</span>get_len<span class="token punctuation">(</span><span class="token punctuation">)</span><span class="token punctuation">:</span> <span class="token keyword">print</span><span class="token punctuation">(</span><span class="token string">"插入结点位置不合理"</span><span class="token punctuation">)</span> <span class="token keyword">return</span> temp <span class="token operator">=</span> self<span class="token punctuation">.</span>head cur_pos <span class="token operator">=</span> <span class="token number">0</span> <span class="token keyword">while</span> temp <span class="token keyword">is</span> <span class="token operator">not</span> Node<span class="token punctuation">:</span> cur_pos <span class="token operator">+=</span> <span class="token number">1</span> <span class="token keyword">if</span> cur_pos <span class="token operator">==</span> pos<span class="token operator">-</span><span class="token number">1</span><span class="token punctuation">:<