如何在py中循环循环以获取字典

Question

So i tried defining a function in which the classroom's names would be generated as a dictionary. But there seems to be an error in it and i can't find out what.

This is the syntax

def classroom():
    noofclass=int(input('Enter the number of classes:'))

    noofdivision=int(input('Enter the number of divisions: '))

    x={}
    for i in range(1,noofclass + 1):

        for j in range(1,noofdivision + 1):
            dict1={i:j}
            x.update(dict1)


    print(x)

classroom()

This is the output

Enter the number of classes:2
Enter the number of divisions: 2
{1: 2, 2: 2}

The division or subclasses for some reason dont take the values other than the value for 'noofdivision'. Can you explain why and how to fix this error.

Answer 1

Since a dictionary is a unique collection of keys, the second j iteration for each i overwrites the first iteration.

So for i=1 , key 1 is created with value 1 and then, in the second iteration of j loop, the key 1 will be overwritten by 2 .

For your use case, x should be a list of dicts . Try:

def classroom():
    noofclass=int(input('Enter the number of classes:'))
    noofdivision=int(input('Enter the number of divisions: '))
    x=[]
    for i in range(1,noofclass + 1):
        for j in range(1,noofdivision + 1):
            x.append({i:j})
    print(x)

classroom() # output: [{1:1},{1:2}, {2:1}, {2:2}]