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.
class Solution {
public int reverse(int x) {
int result = 0;
while (x != 0) {
int mod = x % 10;
x = x / 10;
if (result > Integer.MAX_VALUE / 10 || result < Integer.MIN_VALUE / 10) return 0;
result = result * 10 + mod;
}
return result;
}
}
为了防止溢出,在运算中应该加以判断进行标记,如果溢出那么直接返回。