public int isOver() {
        if (humanPlayer.miles == 1000)
            return HUMAN;
        else if (cpuPlayer.miles == 1000)
            return CPU;
        else if (humanPlayer.miles >= 900 && cpuPlayer.miles == 0)
            return HUMAN;
        else if (cpuPlayer.miles >= 900 && humanPlayer.miles == 0)
            return CPU;
        else
            return 0;
    }