Green Screen Algorithm

// write your code here
var fgImage = new SimpleImage("drewRobert.png");
var bgImage = new SimpleImage("dinos.png");
var output = new SimpleImage( fgImage.getWidth(), fgImage.getHeight());
for (var pixel of fgImage.values()){
    if (pixel.getGreen() >= pixel.getRed() + pixel.getBlue()){
        var x = pixel.getX();
        var y = pixel.getY();
        var bgPixel = bgImage.getPixel(x,y);
        output.setPixel(x,y,bgPixel);
    }
    else {
        output.setPixel(pixel.getX(),  pixel.getY(),   pixel);
    }
}
print (output);