Why is my solution is wrong?

and I couldn’t understand the answer.
I have found another solution.
Hi Maho
You have already found out, the issue is with your code
x.append(row(i))
.
In the solution code,num_rows
is 3
and num_cols
is 4
. So the first for loop will iterate through each row and the second for loop will traverse through each column of the current row.
hence, matrix[row][col]
will fetch us each and every item in the matrix.
matrix[0][0]
is 0
, matrix[0][1]
is 9
, matrix[0][2]
is 5
, matrix[0][3]
is 4
and so on.
total += matrix[row][col]
will get us the sum of all the values.
Hope it’s clear now.
Thanks.