Package g2401_2500.s2420_find_all_good_indices

Class Solution

  • public class Solution
extends Object
    2420 - Find All Good Indices.

    Medium

    You are given a 0-indexed integer array nums of size n and a positive integer k.

    We call an index i in the range k <= i < n - k good if the following conditions are satisfied:

    • The k elements that are just before the index i are in non-increasing order.
    • The k elements that are just after the index i are in non-decreasing order.

    Return an array of all good indices sorted in increasing order.

    Example 1:

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

    Output: [2,3]

    Explanation: There are two good indices in the array:

    • Index 2. The subarray [2,1] is in non-increasing order, and the subarray [1,3] is in non-decreasing order.

    • Index 3. The subarray [1,1] is in non-increasing order, and the subarray [3,4] is in non-decreasing order.

    Note that the index 4 is not good because [4,1] is not non-decreasing.

    Example 2:

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

    Output: []

    Explanation: There are no good indices in this array.

    Constraints:

    • n == nums.length
    • 3 <= n <= 105
    • 1 <= nums[i] <= 106
    • 1 <= k <= n / 2

    • Constructor Detail

      • Solution

        public Solution()

    • Method Detail

      • goodIndices

        public List<Integer> goodIndices​(int[] nums,
                                 int k)