How to fill 2D Array diagonally?

#1

Normally, we traverse a 2D Array row wise or column wise but here we need to fill array elements diagonally. How to traverse array diagonally?

#2

to move diagonal from (i,j) we have to increase i and j both
(i+1,j+1)

do it like this

for(int j=0;j<n;j++){
    int x =0,y=j;
    while(x<n){
        
        // your code

        x++;
        y++;
    }
}