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reverse integer(leetcode

admin 11月 13, 2020 0

Problem

Problem

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

Python solution

import ctypes

class Solution:
    def reverse(self, x):
        rev = 0
        while(x != 0):
            if(x < 0):
                rev = rev * 10 - abs(x) % 10
            else:
                rev = rev * 10 + x % 10
            if ((rev < -(2**31)) or (rev > (2**31)-1)):
                return 0
            x = int(float(x) / 10)
        return rev

if __name__ == "__main__":
    raw_number = int(input("Input number: "))
    modified_number = ctypes.c_long(raw_number & 0xFFFFFFFF).value
    print(Solution().reverse(modified_number))