Contains Duplicate II

Given an array of integers and an integer k, return true if and only if there are two distinct indices i and j in the array such that nums[i] = nums[j] and the difference between i and j is at most k.

 

public class Solution {
    public boolean containsNearbyDuplicate(int[] nums, int k) {
        Map<Integer,Integer> map = new HashMap<>();
        for(int i=0;i<nums.length;i++) {
            if(map.containsKey(nums[i])&&(i-map.get(nums[i]))<=k) return true;
            else map.put(nums[i],i);
        }
        return false;
    }
}