Check Duplicate II

出处

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.

Solution

Complexity

Code

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])){
                int pre = map.get(nums[i]);
                if(i-pre<=k)
                    return true;
            }
     
            map.put(nums[i], i);
        }
     
        return false;
    }
}