Find All K Distant Indices In An Array · Interview Problem

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Leetcode

Medium

Arrays

Hash Maps

Find All K Distant Indices In An Array

Return every array index whose distance to any occurrence of a given key is at most k.

Acceptance 100%

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Problem Statement

Given an integer array nums, an integer key, and an integer k, find all indices i such that there exists at least one index j with nums[j] == key and |i - j| <= k.

Return the indices in increasing order.

The task is to identify all positions that are within distance k of any occurrence of key in the array.

Input Format

An integer array nums
An integer key
An integer k

Output Format

A list of all valid indices in increasing order

Constraints

1 <= nums.length
0 <= k
nums[i] and key are integers
All returned indices must satisfy the distance condition for at least one occurrence of key

Examples

Sample cases returned by the problem API.

Example 1

Input

nums = [3,4,9,1,3,9,5], key = 9, k = 1

Output

[1,2,3,5,6]

Explanation

Indices 1, 2, and 3 are within distance 1 of the key at index 2. Indices 5 and 6 are within distance 1 of the key at index 5.

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