python key=lambda 元素: 元素[字段索引]用法

key=lambda 元素: 元素[字段索引]
x:x[]字母可以随意修改，比如改成y:y[]也行，排序方式按照中括号[]里面的维度进行排序，[0]按照第一维排序，[1]按照第二维排序，[2]按照第三维排序，依此类推。

如二维：

class Solution:
    @staticmethod
    def test(lst):
        res1 = min(lst, key=lambda x: x[0])
        print(res1)

        res2 = max(lst, key=lambda y: y[1])
        print(res2)

        res3 = sorted(lst, key=lambda x: x[0])
        print(res3)


if __name__ == '__main__':
    s = Solution()
    lst = [(1, 0), (8, 1), (3, 2), (4, 3), (11, 4), (6, 5), (7, 6), (9, 7), (9, 8)]
    s.test(lst)

三维：

class Solution:
    @staticmethod
    def test(lst):
        res1 = min(lst, key=lambda x: x[1])
        print(res1)

        res2 = max(lst, key=lambda y: y[0])
        print(res2)

        res3 = sorted(lst, key=lambda x: x[2])
        print(res3)


if __name__ == '__main__':
    s = Solution()
    lst = [(1, 0, 'b'), (8, 1, 'c'), (3, 2, 'a'), (4, 3, 'z'), (11, 4, 'q'), (6, 5, 'e'), (7, 6, 'f'), (9, 7, 'g'), (9, 8, 's')]
    s.test(lst)