使用 n 输入在 python 中递归 function

Question

I want to make a program, the output like

I am confused concerning for n looping, my code right now looks like this

def menu(n):
    return append(n, 0, 0)

def append(n, parent, label):

    if n == 0:
        return 1
    elif n > 0:
        id = (n-n)+1
        parent = input("parent :")
        label = input("label :")
        print(id)
        print(parent)
        print(label)
        menu(n-1)

menu(
    int(input())
)

Can anyone help me how to make output using n input?

Answer 1

Based on my understanding of your code, I tried to apply it in a different code. Here is my simple suggestion:

ndata = int(input("total of input: "))
data = {'id': [], 'parent': [], 'label': []}
for i in range(ndata):
    parent = int(input("parent: "))
    label = input("label: ")
    data['id'].append(i+1)
    data['parent'].append(parent)
    data['label'].append(label)

# print data
print('### print data ###')
print(f'total of data: {ndata}')
for i in range(len(data['id'])):
    print(data['id'][i], data['parent'][i], data['label'][i])

If you run it on your terminal, you can input the data dan print the output. Here is my case:

total of input: 8
parent: 0
label: menu_1
parent: 0
label: menu_2
parent: 1
label: menu_3
parent: 1
label: menu_4
parent: 2
label: menu_5
parent: 3
label: menu_6
parent: 0
label: menu_7
parent: 2
label: menu_8
### print data ###
total of data: 8
1 0 menu_1
2 0 menu_2
3 1 menu_3
4 1 menu_4
5 2 menu_5
6 3 menu_6
7 0 menu_7
8 2 menu_8

Answer 2

Here is a demo reading the lines from a list in the code. Presumably, you can figure out how to read from a file instead.

lines = [
    '8',
    '1 0 menu_1',
    '2 0 menu_2',
    '3 1 menu_3',
    '4 1 menu_4',
    '5 2 menu_5',
    '6 3 menu_6',
    '7 0 menu_7',
    '8 2 menu_8',
]

toplevel = []
index = {}

for line in lines[1:]:
    idx, parent, name = line.strip().split()
    new = [name, []]
    index[idx] = new
    if parent == '0':
        toplevel.append( new )
    else:
        pitem = index[parent]
        pitem[1].append( new )

def print_menu( level, items ):
    for item in items:
        print( ' '*level*4 + item[0] )
        print_menu( level+1, item[1] )

print_menu( 0, toplevel )

Output:

[timr@Tims-Pro:~/src]$ python x.py
menu_1
    menu_3
        menu_6
    menu_4
menu_2
    menu_5
    menu_8
menu_7
[timr@Tims-Pro:~/src]$