Contains Duplicate II

Source

• leetcode: Contains Duplicate II

Given an array of integers and an integer k, find out whether 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.

java

public class Solution {
    public boolean containsNearbyDuplicate(int[] nums, int k) {
        HashMap<Integer, Integer> map = new HashMap<Integer, Integer>();

        for(int i=0; i<nums.length; i++){
            if(!map.containsKey(nums[i]) || i-map.get(nums[i])>k){
                map.put(nums[i], i);
            }
            else{
                return true;
            }
        }
        return false;        
    }
}