void setup() {
  size(200,200);
  smooth();
  frameRate(30);
}


void draw() {
  float grade = random(0,100);
  if (grade >= 90) {
    println( "Assign letter grade A.");
  } 
  else if (grade >= 80) {
    println ( "Assign letter grade B.");
  } 
  else if (grade >= 70) {
    println( "Assign letter grade C.");
  } 
  else if (grade >= 60) {
    println( "Assign letter grade D.");
  } 
  else {
    println( "Assign letter grade F.");
  }
}