[LeetCode]Reverse Integer

Reverse digits of an integer.

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

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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).

思考：此題想要AC並不難，關鍵在於本身是否想到到splilers中說的那些注意點。

class Solution {
public:
    int reverse(int x) {
        // IMPORTANT: Please reset any member data you declared, as
        // the same Solution instance will be reused for each test case.
		int res = 0;  
		while(x)  
		{  
			res = res*10 + x%10;  
			x /= 10;  
		}  
		return res;  
	}
};