function setup() {  

  createCanvas(400, 400);

  background(204);

}

 function SarahSquare(sqcenterx, sqcentery, p){

  beginShape();

  vertex(sqcenterx-(p/2), sqcentery-(p/2));

  vertex(sqcenterx-(p/2), sqcentery+(p/2));

  vertex(sqcenterx+(p/2), sqcentery+(p/2));

  vertex(sqcenterx+(p/2), sqcentery-(p/2));

  endShape(CLOSE);

 }

function mousePressed() { 

  fill(0);

  textSize(12);

  textAlign(CENTER);

  push();

  stroke('red');

  strokeWeight(4.5);

  point(mouseX, mouseY);

  pop();

  stroke(204);

  strokeWeight(4.5);

  text("(" + floor(mouseX) + ", " + floor(mouseY) + ")", mouseX, mouseY-5);

  print("vertex"+"("+floor(mouseX)+", " + floor(mouseY) + ");");

​

}

function draw(){

  SarahSquare(100, 250, 60)

}