still missing some test cases can anyone catch why ??

static long calc(long a, long b, long c) {
    if(a == Integer.MIN_VALUE || b == Integer.MIN_VALUE || c == Integer.MIN_VALUE)
        return Integer.MIN_VALUE;
    return a * b * c;
}

static long maximumProfit(int[] a) {
    TreeSet<Long> lset = new TreeSet<Long>();
    TreeSet<Long> rset = new TreeSet<Long>();
    for(int i : a)
        rset.add((long)i);

    long max = Long.MIN_VALUE;

    for(int i = 0;i < a.length;i++) {
        rset.remove((long)a[i]);
        long res = Long.MIN_VALUE;

        if(lset.size() > 0 && rset.size() > 0) {
            long a1 = (lset.first() < (long)a[i]) ? lset.first() : Integer.MIN_VALUE;
            long a2 = (lset.lower((long)a[i]) == null) ? Integer.MIN_VALUE : lset.lower((long)a[i]);
            long c1 = (rset.higher((long)a[i]) == null) ? Integer.MIN_VALUE : rset.higher((long)a[i]);
            long c2 = (rset.last() > (long)a[i]) ? rset.last() : Integer.MIN_VALUE;

            res = Math.max(res, calc(a1, (long)a[i], c1));
            res = Math.max(res, calc(a2, (long)a[i], c1));
            res = Math.max(res, calc(a1, (long)a[i], c2));
            res = Math.max(res, calc(a2, (long)a[i], c2));
            //System.out.println("a[i] = " + a[i] + " res = " + res);
            if(res > max)
                max = res;
        }

        lset.add((long)a[i]);
    }

    return max == Long.MIN_VALUE ? -1 : max;
}