Package g2501_2600.s2501_longest_square_streak_in_an_array

Class Solution

java.lang.Object

g2501_2600.s2501_longest_square_streak_in_an_array.Solution

public class Solution
extends Object

2501 - Longest Square Streak in an Array.

Medium

You are given an integer array nums. A subsequence of nums is called a square streak if:

• The length of the subsequence is at least 2, and
• after sorting the subsequence, each element (except the first element) is the square of the previous number.

Return the length of the longest square streak in nums, or return -1 if there is no square streak.

A subsequence is an array that can be derived from another array by deleting some or no elements without changing the order of the remaining elements.

Example 1:

Input: nums = [4,3,6,16,8,2]

Output: 3

Explanation: Choose the subsequence [4,16,2]. After sorting it, it becomes [2,4,16].

• 4 = 2 * 2.

• 16 = 4 * 4.

Therefore, [4,16,2] is a square streak.

It can be shown that every subsequence of length 4 is not a square streak.

Example 2:

Input: nums = [2,3,5,6,7]

Output: -1

Explanation: There is no square streak in nums so return -1.

Constraints:

• 2 <= nums.length <= 105
• 2 <= nums[i] <= 105

Constructor Summary

Constructors

Constructor	Description
Solution()

Method Summary

Modifier and Type	Method	Description
int	longestSquareStreak(int[] nums)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Solution

public Solution()

Method Detail

longestSquareStreak

public int longestSquareStreak(int[] nums)