【LeetCode】Reverse Integer

题目描述

Reverse Integer

 

Reverse digits of an integer.

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

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题目分析

这个题目没什么难度，一个循环搞定

代码示例

#include 
    
     
#include 
     
      

using namespace std;


class Solution {
public:
    int reverse(int x) {
    	int sign = 1;
    	if(x < 0)	x = -x,sign = -1;
    	int ret = 0;
    	while(x>0)
    	{
    		ret = ret * 10 + (x%10);
    		x /= 10;
		}    	
        return ret*sign;
    }
};

void check(int x,int expected)
{
	Solution so;

	if(expected == (so.reverse(x)))
		printf("---------------------passed%5d--%5d \n",expected,(so.reverse(x)));
	else
		printf("---------------------failed%5d--%5d \n",expected,(so.reverse(x)));
}

int main()
{
	check(123,321);
	check(0,0);
	check(1,1);
	check(-123,-321);
	check(+123,321);
	return 0;
} 

     
    

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C++标准函数库

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