Maybe too simple... static int[] solve(int[] a, int[] b) {

    int aliceResult = 0;
    int bobResult = 0;

    for(int i = 0; i < 3; i++)
    {
        if(a[i] > b[i])
        {
            aliceResult++;
        }

        if(a[i] < b[i])
        {
            bobResult++;
        }
    }

    return new int[]{ aliceResult, bobResult};
}