132 Pattern

arraybinary searchstack

Problem Statement

Given an array of n integers nums , a 132 pattern is a subsequence of three integers nums[i] , nums[j] and nums[k] such that i < j < k and nums[i] < nums[k] < nums[j] .

Return true if there is a 132 pattern in nums , otherwise, return false .

Examples

Example 1

Input: nums = [1,2,3,4]
Output: false
There is no 132 pattern in the sequence.

Example 2

Input: nums = [3,1,4,2]
Output: true
There is a 132 pattern in the sequence: [1, 4, 2].

Example 3

Input: nums = [-1,3,2,0]
Output: true
There are three 132 patterns in the sequence: [-1, 3, 2], [-1, 3, 0] and [-1, 2, 0].

Constraints

n == nums.length

1 <= n <= 2 * 10 ^5

-10 ^9 <= nums[i] <= 10 ^9

🤔

Medium

Difficulty

Topic Info

ModuleDSA

CategoryArray

Sub-topicBinary Search