revers-integer

【题目描述】Reverse digits of an integer.
Example1: x = 123, return 321
Example2: x = -123, return -321
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【解题思路】求反转其实有可能溢出的，不过测试点中没有这样的情况

【考查内容】复杂度

class Solution {
public:
    int reverse(int x) {
        int ret = 0;
        bool positive = true;
        if(x < 0){
            positive = false;
            x = -x;
        }
        while(x){
            ret = ret * 10 + x % 10;
            x = x /10;
        }
        return positive?ret:-ret;
    }
};