Why these two functions are giving different output

Python Help
1 
def func1(N,A):
    # prefCount = [[0]*(N+1)]
    prefCount = [[0]*(N+1)] * 11
    for i in range(1,11):
        for j in range(1,N+1):
            if A[j-1] == i:
                prefCount[i][j] = prefCount[i][j-1] + 1
            else:
                prefCount[i][j] = prefCount[i][j-1]
    return prefCount

def func2(N,A):
    prefCount = [[0]*(N+1)]
    # prefCount = [[0]*(N+1)] * 11
    for i in range(1,11):
        tmp = [0] * (N+1)
        for j in range(1,N+1):
            if A[j-1] == i:
                tmp[j] = tmp[j-1] + 1
            else:
                tmp[j] = tmp[j-1]
        prefCount.append(tmp)
    return prefCount


print('Output for Function 1')
print(func1(3,[2,2,1]))
print('\nOutput for Function 2')
print(func2(3,[2,2,1]))

Why these two functions giving different outputs ?

Output:

Output for Function 1
[[0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0]]

Output for Function 2
[[0, 0, 0, 0], [0, 0, 0, 1], [0, 1, 2, 2], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0]]
2

The code prefCount = [[0]*(N+1)] * 11 makes prefCount contain the same list object 11 times. When you edit that list, it will show up in every position in that list.

Reference question on Stack Overflow:

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