Leetcode 219: Contains Duplicate
Given an integer array nums and an integer k, return true if there are two distinct indices i and j in the array such that nums[i] == nums[j] and abs(i - j) <= k.
Example 1:
Input: nums = [1,2,3,1], k = 3
Output: true
Example 2:
Input: nums = [1,0,1,1], k = 1
Output: true
Example 3:
Input: nums = [1,2,3,1,2,3], k = 2
Output: false
Constraints:
1 <= nums.length <= 105-109 <= nums[i] <= 1090 <= k <= 105
public boolean containsNearbyDuplicate(int[] nums, int k) {
Set<Integer> set = new TreeSet<>();
for (int i = 0; i < nums.length; ++i) {
if (set.contains(nums[i])) return true;
set.add(nums[i]);
if (set.size() > k) {
set.remove(nums[i – k]);
}
}
return false;
}
// Time Limit Exceeded.