什麼導致「不支持的操作數類型爲//：'list'和'int'」？

Question

這是我現在的代碼。我試圖將基數排序應用於從文件中讀取的數字列表，並將排序後的列表寫入不同的文件。

from math import log 

b = open("radix.in.txt").readlines() 
a = [int(i) for i in b] 

f = open("radix.out.txt", "w") 
def getIndex(num, base, digit_num): 
    return (num // base ** digit_num) % base 

def newLists(size): 
    return [ [] for i in range(size) ] 

def order(a, base, digit_num): 
    placehold = newLists(base) 
    for num in a: 
     placehold[getIndex(num, base, digit_num)].append(num) 
    return placehold 

def radixSort(a, base): 
    passes = 3 
    new_list = a 
    for digit_num in range(passes): 
     new_list = order(new_list, base, digit_num) 
    list_c = [str(i) for i in new_list] 
    print list_c 

radixSort(a, 10) 

輸入文件只是一個所有的數字列表與一個數字進行排序，每行

回溯：

File "C:\Users\Nolan Caldwell\Desktop\HW5.py", line 23, in radixSort new_list = order(new_list, base, digit_num) 
File "C:\Users\Nolan Caldwell\Desktop\HW5.py", line 16, in order placehold[getIndex(num, base, digit_num)].append(num) 
File "C:\Users\Nolan Caldwell\Desktop\HW5.py", line 8, in getIndex return (num // base ** digit_num) % base 
TypeError: unsupported operand type(s) for //: 'list' and 'int' 

Answer 1

你的功能order()預計整數作爲一個列表第一個參數a，這就是第一次迭代的結果。

但是，order()返回列表的列表，並且在radixSort()的第二次迭代中傳遞新列表而不是a，這就是爲什麼它失敗。