2nd algorithm Number of rows = x is 6 Number of columns = y is 8 Place y black tiles rightward on the first row; Place (x - 1) black tiles going down; At the last tile drawn, place (y - 1) black tiles to the left; At the last tile drawn, place (y - 2) black tiles upwards then go one black tile up; Go (x - 4) down then (y - 3) to the right; Then draw 2 black tiles to the right; Go to the left 4 black tiles; Then go down 1 tile down; Then go (y - 3) to the right; Then draw 2 black tiles to the right;

1st Algorithm Number of rows = x is 7 Number of columns = y is 9 Place y black tiles rightward on the first row; Place (x - 1) black tiles going down; At the last tile drawn, place (y - 1) black tiles to the left; At the last tile drawn, place (y - 2) black tiles upwards then go one black tile up; Go half of (x-1) down and (y-2-3)/2 right Then draw 3 black tiles to the right;