       if (illuminationCount(row, col) > 0) {
         setColor(row, col, getYellow());  // Light you've turned on indirectly.
       } else {
+        anyEmpty = true;
         setColor(row, col, getOff());  // Light that's still off.
       }
     }
   }
+  bool victory = !anyInvalid && !anyEmpty;
+  return victory;
 }
 
 // Color definitions

  colors[index] = color;
}

void updateGridColors() {
  for (int index = 0; index < GRIDSIZE * GRIDSIZE; index++) {
    int row = getRow(index);
    int col = getCol(index);

}

// Arduino setup() and loop()
void setup() {
  Serial.begin(9600); 
  pinMode(LED_BUILTIN, OUTPUT);

