       continue;
     } else if (isSwitchOn(row, col)) {
       if (illuminationCount(row, col) > 1) {
+        anyInvalid = true;
         setColor(row, col, getRed());  // Conflicting lights.
         // TODO(dbieber): Send message
         // Serial.println(10);  // Send "Ahhhhhh!" audio signal.

  colors[index] = color;
}

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

  }
}

void loop() {
  delay(20);
  bool victory = update();
  leds.write(colors, STRIP_LENGTH);
  if (victory) {
    delay(500);
    setAllBlue();
  }
}
