int B_SIZE = 6;
int I_SIZE = 12;
int MAP_ROW = 10;
int MAP_COL = 10;

String[] Balloons = new String[B_SIZE];
String[] Icons = new String[I_SIZE];

boolean[][] chinatown;
int[][] icon, nyc;

int WIDTH = 360;
int HEIGHT = 360;

void setup() {
  size(WIDTH, HEIGHT);
  background(255);
  frameRate(24);
  smooth();
  noStroke();
  fill(0,0,0);

  chinatown = new boolean[MAP_ROW][MAP_COL];
  icon = new int[MAP_ROW][MAP_COL];
  nyc = new int[MAP_ROW][MAP_COL];

  for(int i=0;i<B_SIZE;i++) Balloons[i] = "images/i" + i + ".png";
  for(int i=0;i<I_SIZE;i++) Icons[i] = "images/c" + i + ".png";

  for(int i=0;i<MAP_ROW;i++)
    for(int j=0;j<MAP_COL;j++) {
      chinatown[i][j] = false;
      icon[i][j] = int( random(I_SIZE-1) );
      nyc[i][j] = int( random(B_SIZE-1) );
    }  
}

void draw() {
  for(int i=0;i<MAP_ROW;i++)
    for(int j=0;j<MAP_COL;j++) {
      if( chinatown[i][j] ) {
        image(loadImage(Icons[ icon[i][j] ]), j*36, i*36);
      } 
      else {
        image(loadImage(Balloons[ nyc[i][j] ]), j*36, i*36);
      }
    }  
}

void mousePressed() {
  chinatown[mouseY/36][mouseX/36] = true;
}