leetcode-ReverseInteger

Reverse Integer

Reverse digits of an integer.

Example1: x = 123, return 321

Example2: x = -123, return -321

思路

　　本题其实思路很简单，我个人认为只是问题的考察点，应该是对人们对边界的认识。简单的翻转我们都能想到，通过按10取余来获取最后一位,通过除以10来进行移位。一定要记得考虑int的边界。

coding

#include<iostream>
#include "limits.h"

using namespace std;

class Solution {
  public:
    int reverse(int x) {
        long long result = 0;
        while(x != 0)
        {
            result = result * 10 + x % 10;
            x = x/10;
        }
        return (result > INT_MAX || result < INT_MIN) ? 0 : result ;
    }
};

int main(int argc, char *argv[])
{
    Solution s;
    cout << s.reverse(123456) << endl;
    cout << s.reverse(1000) << endl;
    cout << s.reverse(1001) << endl;
    cout << s.reverse(0) << endl;
    cout << s.reverse(-123) << endl;
    cout << s.reverse(-1234) << endl;
    cout << s.reverse(1534236469) << endl;
    cout << 9646324350+1 << endl;

    return 0;
}

github

github代码链接