Reverse digits of an integer.
Example1: x = 123, return 321
Example2: x = -123, return -321
class Solution {
public:
int reverse(int x) {
int res = 0;
while (x != 0) {
if (abs(res) > INT_MAX / 10) return 0;
res = res * 10 + x % 10;
x /= 10;
}
return res;
}
};