Question 7 of leetcode, reverse integer

Question

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 shoshould 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 can you handle such cases?

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

Question

Returns an integer in the reverse format. The positive and negative values remain unchanged.

Answer:

class Solution {public:    int reverse(int x) {        int nReverse = 0;        while (x != 0) {            nReverse = nReverse * 10 + x % 10;            x = x / 10;        }        return nReverse;    }};