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.
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:
def reverse(self, x: int) -> int:
sign = -1 if x < 0 else 1
x *= sign
res = 0
while x > 0:
res = (res * 10) + x % 10
x = x // 10
res*=sign
return res if abs(res) <= (2 ** 31) else 0
Space Complexity : O(1)
Time Complexity : O(n)
