<canvas width="600" height="400"></canvas>
<script>
function dibujarCuadrado(x,y,color){
var pantalla = document.querySelector("canvas")
var pincel = pantalla.getContext("2d")
pincel.fillStyle = color
pincel.fillRect(x,y,50,50)
pincel.strokeStyle = "black"
pincel.strokeRect(x,y,50,50)
}
var x = 0
while(x < 600){
dibujarCuadrado(x,0,"red");
dibujarCuadrado(x,50,"yellow");
dibujarCuadrado(x,100,"green");
x = x + 50
}
