219. Contains Duplicate II | LeetCode | Top Interview 150 | Coding Questions

Problem Link

https://leetcode.com/problems/contains-duplicate-ii/

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Detailed Step-by-Step Explanation

https://leetcode.com/problems/contains-duplicate-ii/solutions/7500664/most-optimal-solution-all-languages-beat-nq7m

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Solution

class Solution {
    public boolean containsNearbyDuplicate(int[] nums, int k) {

        Map<Integer, Integer> map = new HashMap<>();

        int idx = 0;

        for(int i : nums) {
            if(map.containsKey(i) && Math.abs(idx - map.get(i)) <= k) {
                return true;
            }
            map.put(i, idx);
            idx++;
        }

        return false;
    }
}