Given an array of integers, find out whether there are two distinct indices i and j in the array such that the absolute difference between nums[i] and nums[j] is at most t and the absolute difference between i and j is at most k.
类似题目
思路：维持一个大小为k的窗口，由左向右在nums中移动。对于nums[i]，只要查找其之前的元素中是否存在大小范围在[nums[i] - t,nums[i] + t]的元素，如果存在就返回true。还要注意整数的溢出问题，比如下面的测试用例：
[0,2147483647]
1
2147483647
代码：
1 public class Solution { 2 public boolean containsNearbyAlmostDuplicate(int[] nums, int k, int t) { 3 if (nums == null || nums.length == 0 || k <= 0) 4 return false; 5 TreeSet<Long> ts = new TreeSet(); 6 for (int i = 0; i < nums.length; ++i) { 7 Long right = ts.floor((long) nums[i] + t); 8 Long left = ts.ceiling((long) nums[i] - t); 9 if (right != null && left != null && right >= left) 10 return true; 11 ts.add((long) nums[i]); 12 if (i >= k)//i >= k说明nums[i]之前至少已经有k各不相同的元素（否则早就返回true） 13 ts.remove((long) nums[i - k]); 14 // //将上面的if改写成以下条件也是正确 15 // if (ts.size() >= k)// 16 // ts.remove((long) nums[i - k]); 17 18 } 19 return false; 20 } 21 }