334 Increasing Triplet Subsequence LeetCode




Given an unsorted array return whether an 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.

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

Example 1:

Input: [1,2,3,4,5]
Output: true

Example 2:

Input: [5,4,3,2,1]
Output: false
Code--------------------------------------------------
class Solution {
    public boolean increasingTriplet(int[] nums) {
        int m1=Integer.MAX_VALUE;
        int m2=Integer.MAX_VALUE;
        int m3=Integer.MAX_VALUE;
        for(int i:nums){
            if(i<=m1) m1=i;
            else if(i<=m2 && i>=m1) m2=i;
            else if(i<=m3 && i>=m2&& i>=m1) return true;
        }
        return false;
    }
}