public boolean checkVertical() {
        for (int col = 0; col < numColumns; col++) {
            for (int row = 0; row < numRows - 3; row++) {
                int curr = gameGrid[col][row].getState();
                if (curr > 0 //circle is red or yellow
                        && curr == gameGrid[col][row + 1].getState() //increment the row
                        && curr == gameGrid[col][row + 2].getState() //but stay in the same column
                        && curr == gameGrid[col][row + 3].getState()) {
                    winX = col;
                    winY = row;
                    game.setGameIsOver(true);
                    return true;
                }
            }
        }
        return false;
    }