java.lang.Object
g2501_2600.s2537_count_the_number_of_good_subarrays.Solution

public class Solution extends java.lang.Object
2537 - Count the Number of Good Subarrays.

Medium

Given an integer array nums and an integer k, return the number of good subarrays of nums.

A subarray arr is good if it there are at least k pairs of indices (i, j) such that i < j and arr[i] == arr[j].

A subarray is a contiguous non-empty sequence of elements within an array.

Example 1:

Input: nums = [1,1,1,1,1], k = 10

Output: 1

Explanation: The only good subarray is the array nums itself.

Example 2:

Input: nums = [3,1,4,3,2,2,4], k = 2

Output: 4

Explanation: There are 4 different good subarrays:

  • [3,1,4,3,2,2] that has 2 pairs.

  • [3,1,4,3,2,2,4] that has 3 pairs.

  • [1,4,3,2,2,4] that has 2 pairs.

  • [4,3,2,2,4] that has 2 pairs.

Constraints:

  • 1 <= nums.length <= 105
  • 1 <= nums[i], k <= 109
  • Constructor Summary

    Constructors
    Constructor
    Description
     
  • Method Summary

    Modifier and Type
    Method
    Description
    long
    countGood(int[] nums, int k)
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
  • Constructor Details

    • Solution

      public Solution()
  • Method Details

    • countGood

      public long countGood(int[] nums, int k)