NC112 进制转换(python)

#
# 进制转换
# @param M int整型 给定整数
# @param N int整型 转换到的进制
# @return string字符串
#
class Solution:
    def solve(self , M , N ):
        # write code here
        t = "0123456789ABCDEF"
        flag = False
        if M == 0: return 0
        res = ""
        if M < 0:
            flag = True
            M = -M
        while M > 0:
            res += t[M%N]
            M //= N
        if flag:
            res += ‘-‘
        return res[::-1]