Can someone spot the bug in this program?

Question

Here is the problem https://www.geeksforgeeks.org/subset-sum-problem-dp-25/

I can't figure out where the code is going wrong

arr = [2, 7, 3, 8]
k = 5
n = 4

# initialisation
dp = [[0]*(k+1)]*(n+1)

for x in range(n+1):
    dp[x][0] = 1 

#tabulation 
for i in range(1, n+1): 
    for j in range(1, k+1):  
        if arr[i-1]>j:
            dp[i][j] = dp[i-1][j]
        else:
            dp[i][j] = dp[i-1][j] or dp[i-1][j-arr[i-1]]

for m in range(n+1):
    for n in range(k+1):
        print(dp[m][n], end=" ")
    print()

Answer 1

I'm unsure what the code is doing, but the line

dp = [[0]*(k+1)]*(n+1)

is definitely wrong, as it is taking n+1 references to one list. See below:

>>> k=3
>>> n=3
>>> dp = [[0]*(k+1)]*(n+1)
>>> dp
[[0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0]]
>>> dp[0][0]=1
>>> dp
[[1, 0, 0, 0], [1, 0, 0, 0], [1, 0, 0, 0], [1, 0, 0, 0]]