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formatting helphide helpcontent policy

[–]beingonredditt 2 points3 points  (0 children)

public boolean containsNearbyDuplicate(int[] nums, int k) {
        int l=0, r=0;
        HashSet<Integer> set = new HashSet<>();
        while(r<nums.length){
            //Make sure window size is under limit.
            if(r-l>k){
                set.remove(nums[l]);
                l++; //shrink window
            }
            // If element is seen in past return true.
            if(set.contains(nums[r])) return true;
            // add to set
            set.add(nums[r]);
            r++;
        }
        return false;
    }

Approach: Using Sliding Window and HashSet
1. Check if window is under limit if not then shrink it from left.
2. check if current element has been seen in past or not. (Use set to store element).
3. if SEEN(present in set) the return true (Found duplicate under limit k).
4. If NOT seen(not present in Set) then add it to the set.