LeetCode 75 C++ | Step-by-Step Solutions (LAN Academy) - 334 Increasing Triplet Subsequence (C++) | Greedy (Two Vars) | LeetCode 75 #08

Do you want to master LeetCode problems and think like a real interviewer? In this video, we solve LeetCode 334 – Increasing Triplet Subsequence in C++, using an elegant O(n) one-pass solution that needs O(1) extra space. Most people try DP or sorting and overcomplicate it. The interview-ready insight is simpler: you don’t need the actual triplet — you only need to know whether it can exist by tracking the best candidates for the first two values. What you'll learn: How to detect an increasing triplet efficiently in one pass The core insight: track two smallest candidates (first, second) Why this guarantees correctness without building subsequences Edge cases that break naive solutions (duplicates, decreasing arrays, late triplets) Core idea (quick intuition): Keep: first = smallest number seen so far second = smallest number greater than first When you find a number x that is greater than both, you have a valid increasing triplet. Time complexity: O(n) Space complexity: O(1) Watch the full LeetCode 75 Series: https://lanacademy-school.thinkific.com/courses/leetcode75 Problem Link: https://leetcode.com/problems/increasing-triplet-subsequence/ This video is for: Developers preparing for coding interviews Students learning array patterns and greedy logic in C++ Anyone improving algorithmic thinking with clean constraints-based solutions Follow LAN Academy: Website: https://lanacademy-school.thinkific.com YouTube: @lanacademy9521 Twitter: https://x.com/SolutionsLan #LeetCode #cpp #DSA #CodingInterview #Algorithms #LANAcademy #LeetCode75 #InterviewPrep #Arrays #Greedy #OnePass #334 @reper #foryou #viral #reper #urmaritori #for