String prize = "";                   //var to remember cell contents

void board( ) {
  fill(0);							  // draw the board
  stroke(250, 250, 0);
  strokeWeight(5);
  rect(150, 150, 750, 766);
  fill(0,255,0);					// draw the green button
  stroke(0);
  strokeWeight(5);
  rect(50, 80, 50, 50);
  noStroke( );
  prize( );							// call the function to display cell content
}

void prize ( ) {
   //the first part of this function places a "prize" in each cell
   //the second part replaces one of them with a "golden prize"
   // Notice how the row and col variables are used to translate between
   // the list of prizes, which is 1-dimensional, and the 2-dimensional
   // grid of the game board
    int row, col, newworld;
    for (int i = 0; i < 25; i = i +1) { // Need 25 prizes for board
    if (random(0,2) < 1 ) {            //Is it blue or green?
        fill(0,0,255);                 //blue
	    prize = prize + 'B';           //record it
    } else {
        fill(0,255,0);                 //green
        prize = prize + 'G';           //record it
    }
        row = i % 5;                   //what row is it in?
        col = int(i/5);                //what col is it in?
        ellipse(225+row*150, 225+col*150, 20, 20);  //draw it
  }
  
  newworld = int(random(1,25));        //Where is exit to new world?
  fill(255,255,0);                     //Set color to gold
  row = newworld % 5;                  //Figure it's row
  col = int(newworld/5);               //Figure it's col
  ellipse(225+row*150, 225+col*150, 20,20);  // draw it
    //Now pull apart the prize string and stick the y for yellow
    //into it at the right place
  prize = prize.substring(0,newworld) + "y" + prize.substring(newworld+1,prize.length());
  println(prize);                       //Watch it work!
}