문제 설명 문제 Given a signed 32-bit integer x, return x with its digits reversed. If reversing x causes the value to go outside the signed 32-bit integer range [-231, 231 - 1], then return 0. Assume the environment does not allow you to store 64-bit integers (signed or unsigned). 입출력 예시 Input: x = 123 Output: 321 Input: x = -123 Output: -321 Input: x = 120 Output: 21 제한사항 -2^31