992. Subarrays with K Different Integers ¶
Problem
Given an integer array nums
and an integer k
, return the number of good subarrays of nums
.
A good array is an array where the number of different integers in that array is exactly k
.
- For example,
[1,2,3,1,2]
has3
different integers:1
,2
, and3
.
A subarray is a contiguous part of an array.
Example 1:
Input: nums = [1,2,1,2,3], k = 2 Output: 7 Explanation: Subarrays formed with exactly 2 different integers: [1,2], [2,1], [1,2], [2,3], [1,2,1], [2,1,2], [1,2,1,2]
Example 2:
Input: nums = [1,2,1,3,4], k = 3 Output: 3 Explanation: Subarrays formed with exactly 3 different integers: [1,2,1,3], [2,1,3], [1,3,4].
Constraints:
1 <= nums.length <= 2 * 104
1 <= nums[i], k <= nums.length