题目描述 定义栈的数据结构，请在该类型中实现一个能够得到栈最小元素的min函数。 解题思路 用一个栈stack保存数据，用另外一个栈temp保存依次入栈最小的数 比如，stack中依次入栈 5, 3, 4, 10, 2,…

1、题目描述 Given an unsorted integer array, find the smallest missing positive integer. Example 1: Input: [1,2,0] …

130. Surrounded Regions 题目 Given a 2D board containing 'X' and 'O' (the letter O), capture all regions surroun…

  In a 2D grid from (0, 0) to (N-1, N-1), every cell contains a 1, except those cells in t…

Candy There are N children standing in a line. Each child is assigned a rating value. You are giving candies t…

Given two words word1 and word2, find the minimum number of steps required to convert word…

这是悦乐书的第289次更新，第307篇原创 01 看题和准备 今天介绍的是LeetCode算法题中Easy级别的第156题（顺位题号是686）。给定两个字符串A和B，找到A必须重复的最小次数，使得B是它的子字符串。 如果…

DP解法 时间复杂度是O(n) 极简版代码 注意事项 ret_max 的初始值应该是nums[0],留给朋友们思考为什么. class Solution(object): def maxSubArray(self, nu…

  Implement a basic calculator to evaluate a simple expression string. The expression string contains onl…

  Note: For the coding companion problem, please see:  Encode and Decode TinyURL. How would you desi…

  In a given array nums of positive integers, find three non-overlapping subarrays with maximum…

  We have two special characters. The first character can be represented by one bit 0. The second ch…