TinkerableArray.pde

int rows = 10;
int columns = 12;
int[] circles = new int[rows*columns];
int index;
int spacing = 50;
int circleSize = 6;

void setup()
{
  
  circles[16] = 255;
  
  
  size(500, 500);
  background(200);
  for(int i=0;i<rows;i++)
  {
     for(int j=0;j<columns;j++)
     {
        fill(circles[index]);
        ellipse(i*spacing, j*spacing, circleSize, circleSize);
        index++;
     } 
  }
}

void loop()
{
  
}