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# 220. 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 **absolute** difference between **nums\[i]** and **nums\[j]** is at most t and the **absolute** difference between i and j is at most k.

**Example 1:**

```
Input: nums = [1,2,3,1], k = 3, t = 0
Output: true
```

**Example 2:**

```
Input: nums = [1,0,1,1], k = 1, t = 2
Output: true
```

**Example 3:**

```
Input: nums = [1,5,9,1,5,9], k = 2, t = 3
Output: false
```

```cpp
bool containsNearbyAlmostDuplicate(vector<int>& nums, int k, int t) { // time: O(nlogk); space: O(k)
    if (nums.empty() || k < 1 || t < 0) return false;
    set<long> st;
    for (int i = 0; i < nums.size(); ++i) {
        if (i > k) st.erase(nums[i - k - 1]); // maintain set size to k
        auto it = st.lower_bound((long)nums[i] - t);
        if (it != st.end() && *it - nums[i] <= t) return true;
        st.insert(nums[i]);
    }
    return false;
}
```