fullscreen size(500,500);
background(255);
for (int i = 10; i < height; i = i+20) {
fill (0,0,255);
rect(0,i,10,10);
}
for(int i = 0; i < width; i=i+20) {
fill(0);
rect(i,50,10,10);
}
for (int i = 10; i < width; i = i+20) {
fill (0,255,0);
rect(i,50,10,10);
}
for (int i = 00; i < height; i = i+20) {
fill (255,0,0);
rect(0,i,10,10);
}