$ cat ./coding/405-convert-a-number-to-hexadecimal.md

────────────────────────────────────────────────────────────

405. Convert a Number to Hexadecimal

💡

這個題目有一個知識點需要先複習：「二補數」

class Solution:
    def toHex(self, num: int) -> str:
    
        if num == 0:
            return '0'
    
        if num < 0:
            num = (1 << 32) + num
        
        hex_digits = '0123456789abcdef'
        hex_num = ''
        
        while num > 0:
            digit = num % 16
            hex_digit = hex_digits[digit]
            hex_num = hex_digit + hex_num
            num //= 16
        
        return hex_num

$ ls ./coding/ | grep -v 405-convert-a-number-to-hexadecimal