added Function

Author: mauricechouam

README.md

@@ -454,6 +454,17 @@ Input: nums = [5,4,3,2,1]
 Output: false
 Explanation: No triplet exists.
 
+## 43) [Increasing Triplet Subsequence](https://github.com/mauricechouam/Leetcode-training/blob/main/Increasing%20Triplet%20Subsequence/code.js)
+Given an integer array nums, return true if there exists a triple of indices (i, j, k) such that i < j < k and nums[i] < nums[j] < nums[k]. If no such indices exists, return false.
+Example 1:
+Input: nums = [1,2,3,4,5]
+Output: true
+Explanation: Any triplet where i < j < k is valid.
+Example 2:
+Input: nums = [5,4,3,2,1]
+Output: false
+Explanation: No triplet exists.
+