Leetcode:increasing Triplet subsequence

Increasing Triplet subsequence


Total Accepted: 14818 Total Submissions: 43443 Difficulty: Medium

Given an unsorted array return whether a increasing subsequence of length 3 exists or not in the array.

Formally the function should:

Return True if there exists I, J, K
such that Arr[i] < arr[j] < arr[k] given 0≤ i < J < k ≤ n-1 else return false.

Your algorithm should run in O (n) time complexity and O (1) space complexity.

Examples:
Given [1, 2, 3, 4, 5] ,
Return true .

Given [5, 4, 3, 2, 1] ,
Return false .

Credits:
Special thanks to @DjangoUnchained for adding this problem and creating all test cases.

Subscribe to see which companies asked this question

Hide Similar Problems(M) longest increasing subsequence

Java code:

public class Solution {public    Boolean increasingtriplet (int[] nums) {                int max = (1<<31)-1;        int mid = (1<<31)-1;                for (int num:nums) {            if (num <= mid)                mid = num;            else if (num <= max)                max = num;            else                return true;        }                return false;    }}

Leetcode:increasing Triplet subsequence