LargestNumber.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# @Time    : 2019/11/12 21:03
# @Author  : tc
# @File    : LargestNumber.py
"""
题号 179 最大数
给定一组非负整数，重新排列它们的顺序使之组成一个最大的整数。

示例 1:

输入: [10,2]
输出: 210
示例 2:

输入: [3,30,34,5,9]
输出: 9534330

使用python的魔法方法
参考:https://leetcode-cn.com/problems/largest-number/solution/zi-ding-yi-pai-xu-gui-ze-by-powcai/

"""
from typing import List

class LargerNumKey(str):
    def __lt__(x, y):
        return x+y > y+x


class Solution:
    def largestNumber(self, nums: List[int]) -> str:
        largest_num = ''.join(sorted(map(str, nums), key=LargerNumKey))
        return '0' if largest_num[0] == '0' else largest_num


if __name__ == '__main__':
    solution = Solution()
    nums = [0]
    print(solution.largestNumber(nums))