Python列表——去重和添加子列表元素

Question

输入:

a = [[['a','b'],3],[['b','a'],9],[['b','z'],4] ]

期望的输出(不考虑顺序去重并添加整数)

[[['a','b'],12],[['b','z'],4]]

这当然行不通:

a2 = [sorted(list) for list in [i[0] for i in a]]

print(a2)

[['a', 'b'], ['a', 'b'], ['b', 'z']]

当然可以去重:

a3= [] 

for i in a2: 
    if i not in a3: 
       a3.append(i)

print(a3)

[['a', 'b'], ['b', 'z']]

当然，我正在丢失子列表的重复数据删除计数。 有什么建议吗？
谢谢。

Answer 1

我想这就是你想要的:

a = [[['a','b'],3],[['b','a'],9],[['b','z'],4]]

# we use a dict to do the job.
# we sort the list of char and change to tuple. So i can be use as key.
dct = {}

for i in a:
    srt = tuple(sorted(i[0]))
    if srt in dct:
        # the tuple of char is already existing as key, just sum int.
        dct[srt]+= i[1]
    else:
        # if not we had a new key
        dct[srt] = i[1]
# Convert the dict to list of list
new_list = [[list(k),v] for k,v in dct.items()]
print(new_list) # [[['a', 'b'], 12], [['b', 'z'], 4]]