<canvas width="600" height="400"></canvas>
<script>
var tela = document.querySelector("canvas");
var pincel = tela.getContext("2d");
function desenhaQuadrado(x,y,cor){
pincel.fillStyle=cor;
pincel.fillRect(x,y,50,50);
pincel.strokeStyle="black";
pincel.strokeRect(x,y,50,50);
}
var x = 0;
for(var x = 0; x < 150; x = x + 50){
desenhaQuadrado(x,0,'green');
desenhaQuadrado(150,0,'white');
}
</script>
