package _219_Contains_Duplicate_2;

import java.util.HashSet;
import java.util.Set;

/*

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. 

*/

public class Solution {
	
	public static boolean containsNearbyDuplicate(int[] nums, int k) {
		Set<Integer> set = new HashSet<>();
		for (int i = 0; i < nums.length; i++) {
			if (i > k) set.remove(nums[i - k - 1]);
			if (!set.add(nums[i])) return true;
		}
		return false;
	}

	public static void main(String[] args) {
		int[] nums = { 1, 2, 3, 1, 5, 6, 7 };
		System.out.println(containsNearbyDuplicate(nums, 3)); // true
 		System.out.println(containsNearbyDuplicate(nums, 2)); // false

	}

}
