Contains Duplicate III

Given an array of integers, find out whether there are two distinct indices i and j in

the array such that the difference between nums[i] and nums[j] is at most t and the

difference between i and j is at most k.

用一个双层循环明显超时。

别人用同样的时间O(nlog(k))，但是用TreeSet实现。TreeSet具有排序功能，能够

返回在某个区间的set。

public boolean containsNearbyAlmostDuplicate(int[] nums, int k, int t) {
if(k<1||t<0)
return false;
TreeSet<Long> set=new TreeSet<>();
for(int i=0;i<nums.length;i++){
long left=(long)nums[i]-t;
long right=(long)nums[i]+t+1;
SortedSet<Long> subSet=set.subSet(left, right);
if(!subSet.isEmpty())
return true;
set.add((long) nums[i]);
if(i>=k)
set.remove((long)nums[i-k]);
}
return false;
}