Reverse Integer

Medium · Bit Manipulation

You are given a signed 32-bit integer. Reverse the order of its decimal digits, keeping the sign, and return the result. If reversing causes the value to fall outside the signed 32-bit integer range (-2147483648 to 2147483647), return 0 instead.

Examples

Input:  x = 123
Output: 321
Why:    Reversing the digits of 123 gives 321, which fits in a 32-bit signed integer.

Input:  x = -120
Output: -21
Why:    The sign is kept, and the trailing zero disappears when the digits 1,2,0 are reversed to 0,2,1.

Input:  x = 1534236469
Output: 0
Why:    Reversing gives 9646324351, which overflows the 32-bit signed range, so the result is 0.

Constraints

-2^31 <= x <= 2^31 - 1

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Practise Reverse Integer

This statement is written for CodeSpeek. The problem is part of the NeetCode 150 list; Watch NeetCode's explanation of Reverse Integer. Reference solutions from the NeetCode repository (MIT) are used to verify our tests.