Hi,
The problem description is in the comments above the solution below.

The problem belongs to Codility, you can try out it yourself on their platform.

/**
 *An array A consisting of N integers is given. A triplet (P, Q, R) is triangular if 0 ≤ P < Q < R < N and:
 *
 *         A[P] + A[Q] > A[R],
 *         A[Q] + A[R] > A[P],
 *         A[R] + A[P] > A[Q].
 *
 * For example, consider array A such that:
 *   A[0] = 10    A[1] = 2    A[2] = 5
 *   A[3] = 1     A[4] = 8    A[5] = 20
 *
 * Triplet (0, 2, 4) is triangular.
 *
 * Write a function:
 *
 *     class Solution { public int solution(int[] A); }
 *
 * that, given an array A consisting of N integers, returns 1 if there exists a triangular triplet for this array and returns 0 otherwise.
 *
 * For example, given array A such that:
 *   A[0] = 10    A[1] = 2    A[2] = 5
 *   A[3] = 1     A[4] = 8    A[5] = 20
 *
 * the function should return 1, as explained above.
 */

import java.util.Arrays;

public class Triangle {
    boolean isTriangular(long p, long q, long r) {
        if (p + q > r && p + r > q && q + r > p) return true;
        return false;
    }

    public int solution(int[] A) {
        Arrays.sort(A);
        for (int i = 0; i < A.length - 2; i++) {
            if (isTriangular(A[i], A[i + 1], A[i + 2])) {
                return 1;
            }
        }
        return 0;
    }
}