matrix

void matrix(int n, int m){
int arr[10][10];
int prime_diagonal = 0;
for (int i = 0; i<n; i++){
    for (int j = 0; j<m; j++){
         if (i == j){
                arr[i][j] = i;
        }
        else if (i>j){
            arr[i][j] = j - i;
        }
        else if (i<j){
            arr[i][j] = i*j;
        }
        cout<<endl;


};
int main()
{
cout<<matrix(3, 5)<<endl;
return 0;}