What is the time complexity of this code? 2d Array

Question

What is the time complexity of this code? I have a 2d array and every time theres a 0 i want to change the value of the entire row and column to zero.

    for(int i=0; i < copy.length; i++){
        for(int j=0; j < copy[0].length; j++){
            if(copy[i][j] == 0){
                for(int z =0; z < copy.length; z++){
                    a[z][j] = 0;
                }
                for(int z = 0; z < copy[0].length; z++){
                    a[i][z] = 0;
                }
            }
        }
    }
    

Answer 1

Worst case => all zeros.
For copy[m][n];

for(int i=0; i < copy.length; i++){ ===> m times 
    for(int j=0; j < copy[0].length; j++){ ===> n times
        if(copy[i][j] == 0){
            for(int z =0; z < copy.length; z++){ ===> m times
                a[z][j] = 0;
            }
            for(int z = 0; z < copy[0].length; z++){ ===> n times
                a[i][z] = 0;
            }
        }
    }
}

Time-complexity = m*n*(m+n) = mn(m+n)