// 1899. Merge Triplets to Form Target Triplet
// A triplet is an array of three integers. You are given a 2D integer array triplets, where triplets[i] = [ai, bi, ci] describes the ith triplet. You are also given an integer array target = [x, y, z] that describes the triplet you want to obtain.
// To obtain target, you may apply the following operation on triplets any number of times (possibly zero):
// Choose two indices (0-indexed) i and j (i != j) and update triplets[j] to become [max(ai, aj), max(bi, bj), max(ci, cj)].
// For example, if triplets[i] = [2, 5, 3] and triplets[j] = [1, 7, 5], triplets[j] will be updated to [max(2, 1), max(5, 7), max(3, 5)] = [2, 7, 5].
// Return true if it is possible to obtain the target triplet [x, y, z] as an element of triplets, or false otherwise.

public class Solution
{
    public bool MergeTriplets(int[][] triplets, int[] target)
    {
        var set = new HashSet<int>();

        foreach (var t in triplets)
        {
            if (t[0] > target[0] || t[1] > target[1] || t[2] > target[2])
                continue;

            for (var i = 0; i < t.Length; i++)
            {
                if (t[i] == target[i])
                {
                    set.Add(i);
                }
            }
        }

        return set.Count == 3;
    }
}