Reverse Integer

MathNumber Theory

Given an integer, return the integer obtained by reversing the digits of the number. If reversing the integer causes it to go out of the range of a 32-bit signed integer (-2^31 to 2^31 - 1), then return 0. Handle negative integers by preserving the negative sign.

Example 1

Input

[
  123
]

Output

321

Explanation. Reversing 123 results in 321.

Example 2

Input

[
  -123
]

Output

-321

Explanation. Reversing -123 should keep the negative sign, resulting in -321.

Example 3

Input

[
  120
]

Output

Explanation. Reversing 120 results in 21 (the leading zero is removed).

Example 4

Input

[
  1534236469
]

Output

Explanation. The reverse of 1534236469 is out of the 32-bit signed integer range, hence it returns 0.

Follow-up: Can you implement the solution without converting the integer to a string or using any string operations?

Constraints:

The function must handle integers within the range `-2^31` to `2^31 - 1`. Negative numbers should maintain their sign after the digits have been reversed.

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