[問題] List.append問題

[pd41987 (Wangkson ^_____^)]

小弟新學Python~
先前在迴圈內使用list.append在list中append list
output出來的值 不知為何會一直重複
並沒有依序加在list的最尾端
請教各位大大~小弟是哪個地方沒有注意到

Output:
Loop 1
Need to add  [-1, 0, 1]
Result  [[-1, 0, 1]]
Loop 2
Need to add  [-1, 0, 1]
Result  [[-1, 1, 0], [-1, 1, 0]]
Loop 3
Need to add  [-1, -1, 2]
Result  [[-1, 2, -1], [-1, 2, -1], [-1, 2, -1]]
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Code:

nums = [-1, 0, 1, 2, -1, -4]
if len(nums) < 3:
    final_answer_list = []
else:
    answer_list = [0,0,0]
    final_answer_list = []
    print(final_answer_list)
    input_length = len(nums)
    z = 0
    for i in range(0,input_length):
        for j in range(0,input_length):
            if j!=i:
                for k in range(0,input_length):
                    if k!=i and k!=j:
                        answer_list[0] = nums[i]
                        answer_list[1] = nums[j]
                        answer_list[2] = nums[k]
                        cum_val = 0
                        for l in range(0,3):
                            cum_val += answer_list[l]

                        if cum_val == 0:
                            z += 1
                            print('Loop',z)
                            answer_list2 = sorted(answer_list)
                            print('Need to add ',answer_list2)
                            final_answer_list.append(answer_list)
                            print('Result ',final_answer_list)

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推 Yshuan: final_answer_list.append(list(answer_list))
→ Yshuan: append進去的一直是同一塊記憶體 需要copy出來
推 cutekid: 推樓上(Y)
推 brightwish: 不對吧 你打need to add answer_list2 可是你append的
→ brightwish: 是answer_list阿... 漏打2吧?
→ pd41987: 感謝一樓大大!! 剛試過沒有問題 List如預期append起來了
→ brightwish: 樓上 我剛測過了 你就是漏打2啦