2443. Sum of Number and Its Reverse

Problem Link

Description

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Given a non-negative integer num, return true if num can be expressed as the sum of any non-negative integer and its reverse, or false otherwise.

 

Example 1:

Input: num = 443
Output: true
Explanation: 172 + 271 = 443 so we return true.

Example 2:

Input: num = 63
Output: false
Explanation: 63 cannot be expressed as the sum of a non-negative integer and its reverse so we return false.

Example 3:

Input: num = 181
Output: true
Explanation: 140 + 041 = 181 so we return true. Note that when a number is reversed, there may be leading zeros.

 

Constraints:

• 0 <= num <= 105

Solution

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Python3

class Solution:
    def sumOfNumberAndReverse(self, num: int) -> bool:
        N = len(str(num))
        
        for x in range(num, num // 2 - 1, -1):
            if x + int(str(x)[::-1]) == num:
                return True
        
        return False