https://practice.geeksforgeeks.org/problems/triplet-sum-in-array-1587115621/1#
Given an array arr of size n and an integer X. Find if there's a triplet in the array which sums up to the given integer X.
Example 1:
Input: n = 6, X = 13 arr[] = [1 4 45 6 10 8] Output: 1 Explanation: The triplet {1, 4, 8} in the array sums up to 13. Example 2:
Input: n = 5, X = 10 arr[] = [1 2 4 3 6] Output: 1 Explanation: The triplet {1, 3, 6} in the array sums up to 10.
Your Task: You don't need to read input or print anything. Your task is to complete the function find3Numbers() which takes the array arr[], the size of the array (n) and the sum (X) as inputs and returns True if there exists a triplet in the array arr[] which sums up to X and False otherwise.
Expected Time Complexity: O(n2) Expected Auxiliary Space: O(1)
Constraints: 1 ≤ n ≤ 103 1 ≤ A[i] ≤ 105