Given a signed 32-bit integer x, return x with its digits reversed. If reversing x causes the value to go outside the signed 32-bit integer range [-231, 231 - 1], then return 0.
Assume the environment does not allow you to store 64-bit integers (signed or unsigned).
Example 1:
Input: x = 123
Output: 321
Example 2:
Input: x = -123
Output: -321
Example 3:
Input: x = 120
Output: 21
Example 4:
Input: x = 0
Output: 0
Constraints:
-231 <= x <= 231 - 1
class Solution {
public:
int reverse(int x) {
int ans = 0;
while (x != 0) {
if (ans > INT_MAX / 10 || (ans == INT_MAX / 10 && x % 10 > INT_MAX % 10))
return 0; // overflow
if (ans < INT_MIN / 10 || (ans == INT_MIN / 10 && x % 10 < INT_MIN % 10))
return 0; // underflow
ans = ans * 10 + x % 10;
x /= 10;
}
return ans;
}
};
