Contains Duplicate III

 1 public class Solution {
 2     public boolean containsNearbyAlmostDuplicate(int[] nums, int k, int t) {
 3         if(nums==null||nums.length<2||k<0||t<0)
 4             return false;
 5      
 6         TreeSet<Long> set = new TreeSet<Long>();
 7         for(int i=0; i<nums.length; i++){
 8             long curr = (long) nums[i];
 9      
10             long leftBoundary = (long) curr-t;
11             long rightBoundary = (long) curr+t+1; //right boundary is exclusive, so +1
12             SortedSet<Long> sub = set.subSet(leftBoundary, rightBoundary);
13             if(sub.size()>0)
14                 return true;
15      
16             set.add(curr);   
17      
18             if(i>=k){ // or if(set.size()>=k+1)
19                 set.remove((long)nums[i-k]);
20             }
21         }
22      
23         return false;
24     }
25 }