SOURCE

let c=[];
function setup(){
    createCanvas(500,500);
    background(220);
    for(let i=0;i<75;i++){
        c[i]=random(255);
    }
}
function draw(){
    for(let i=0;i<25;i++){
        let index=i*3;
        fill(c[index],c[index+1],c[index+2]);
        stroke(c[i]);
        ellipse(i*20+10,250,20,height);
    }
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/p5.js/1.1.9/p5.min.js"></script>