list and dict 自定义排序

list排序

根据list的不同元素排序

>>> pokemon = [
...    ('Charmander', 'Fire', 52),
...    ('Blastoise', 'Water', 83),
...    ('Beedrill', 'Poison', 90),
... ]
>>> sorted(pokemon, key=lambda x: x[2])   # sort by attack power
[('Charmander', 'Fire', 52),
 ('Blastoise', 'Water', 83),
 ('Beedrill', 'Poison', 90)]

自定义函数排序

>>> import functools

def compare(x, y):
	if x[0] > y[0]:
			return 1
	elif x[0] < y[0]:
			return -1
	elif x[0] == y[0]:
		if x[1] >= y[1]:
			return 1
		elif x[1] < y[1]:
			return -1

a = Solution()
A = [(2,3), (1,5), (3,1), (3, 5), (2,9)]
cmp_func = functools.cmp_to_key(compare) 
sorted_list = sorted(A, key=cmp_func)
print(sorted_list)

[(1, 5), (2, 3), (2, 9), (3, 1), (3, 5)]

第一个元素降序排序，第二个元素升序排序

>>> # Sort number in descending order and word in ascending order
>>> sorted(l, key = lambda x: (-x[0], x[1]))
[(3, 'aaa'), (3, 'ab'), (2, 'aaa'), (1, 'bbbb')]