Reverse Integer

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我是靠谱客的博主勤奋飞机，最近开发中收集的这篇文章主要介绍Reverse Integer，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

Reverse digits of an integer.

Example1: x = 123, return 321
Example2: x = -123, return -321

Have you thought about this?

Here are some good questions to ask before coding. Bonus points for you if you have already thought through this!

If the integer's last digit is 0, what should the output be? ie, cases such as 10, 100.

Did you notice that the reversed integer might overflow? Assume the input is a 32-bit integer, then the reverse of 1000000003 overflows. How should you handle such cases?

Throw an exception? Good, but what if throwing an exception is not an option? You would then have to re-design the function (ie, add an extra parameter).

class Solution {
public:
    int reverse(int x) {
        
        int flag = 0;
        if(x < 0)
        {
            flag = -1;
            x = -x;
        }
        
        int result = 0;
        int k = 1;
        vector<int> figure;
        
        while(x / 10 != 0)
        {
            figure.push_back(x % 10);
            x /= 10;
        }
        figure.push_back(x);
        
        for(int i = figure.size()-1; i >= 0; i--, k *= 10)
        {
            result += figure[i] * k;
        }
        
        if(flag == -1)
            result = -result;
            
        return result;
    }

};