Given a 32-bit signed integer, reverse digits of an integer.
Example 1:
Input: 123
Output: 321
Example 2:
Input: -123
Output: -321
Example 3:
Input: 120
Output: 21
Note:
Assume we are dealing with an environment which could only store integers within the 32-bit signed integer range: [−231, 231 − 1]. For the purpose of this problem, assume that your function returns 0 when the reversed integer overflows.
来源:力扣(LeetCode)
链接:https://leetcode-cn.com/problems/reverse-integer
1.整数边界
int 为32位
int max = 0x7fffffff;
int min = 0x80000000;
class Solution {
public:
int reverse(int x) {
int max = 0x7fffffff;
int min = 0x80000000;
long ans = 0;
while (x){
ans = ans * 10 + x % 10;
if (ans > max || ans < min) return 0;
x /= 10;
}
return ans;
}
};