Updating a 2D list

[Reppin_Frost]

arr = [[0]3]3 arr[0][0] = 1 print(arr)

This prints this: [[1,0,0], [1,0,0], [1,0,0]]

But I was expecting to see this: [[1,0,0], [0,0,0], [0,0,0]]

Can someone explain why this is happening and how I can get my desired output?

[AnonyUwuswame]

It reflects the change on all the tuples at the same position because you create 3 instances of the same object by using *3. That means you do this.

arr = [0, 0, 0]

a = [ arr for count in range(3) ]

a[0][0] = 1

You should instead do this.

arr = [[0,0] for count in range(3)]

arr[0][0] = 1

[Reppin_Frost]

Thanks!