题目地址:https://oj.leetcode.com/problems/single-number-ii/
题意:找出唯一一个不重复三次的数
解题思路:这题没O(N)的思路,就参考了晚上的答案
http://www.tuicool.com/articles/fAZZv2a
class Solution {
public:
int singleNumber(int A[], int n) {
int one=0,two=0,three=0;
for(int i = 0; i<n; ++i){
two |= one&A[i];
one ^= A[i];
three = one&two;
one &=~three;
two &=~three;
}
return one;
}
};