LeetCode 筆記 - 7. Reverse Integer

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題目在此 7. Reverse Integer

將數字反轉

解題思維

這題有夠無聊，感覺是要你學會處理 overflow
但以現代語言來說，已經過時

Time complexity: O(1)

程式碼

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class Solution:
    def reverse(self, x: int) -> int:
        
        x = str(x)
        if len(x) < 2:
            return x
        
        if x.startswith('-'):
            x = x[::-1]
            x = f'-{x[:-1]}'
        else:
            x = x[::-1]
        
        x = int(x)
        
        # overflow
        if x >= 2147483651:
            return 0
        if x <= -2147483651:
            return 0
        return x