CF2011F Good Subarray
Description
You are given an integer array $ a $ of size $ n $ .
Let's call an array good if it can be obtained using the following algorithm: create an array consisting of any single integer; and then perform the following operation an arbitrary number of times: choose an element from the already existing array (let's call it $ x $ ) and add $ x $ , $ (x-1) $ , or $ (x+1) $ to the end of the array.
For example, the arrays $ [1, 2, 1] $ , $ [5] $ and $ [3, 2, 1, 4] $ are good, while $ [2, 4] $ and $ [3, 1, 2] $ are not.
Your task is to count the number of good contiguous subarrays of the array $ a $ . Two subarrays that have the same elements but are in different positions of the array $ a $ are considered different.
Input Format
The first line contains a single integer $ t $ ( $ 1 \le t \le 10^4 $ ) — the number of test cases.
The first line of each test case contains a single integer $ n $ ( $ 1 \le n \le 3 \cdot 10^5 $ ).
The second line of each test case contains $ n $ integers $ a_1, a_2, \dots, a_n $ ( $ 1 \le a_i \le n) $ .
Additional constraint on the input: the sum of $ n $ over all test cases does not exceed $ 3 \cdot 10^5 $ .
Output Format
For each test case, print a single integer — the number of good contiguous subarrays of the array $ a $ .
Explanation/Hint
In the first example, the following four subarrays are good:
- from the $ 1 $ -st to the $ 1 $ -st element;
- from the $ 1 $ -st to the $ 2 $ -nd element;
- from the $ 2 $ -nd to the $ 2 $ -nd element;
- from the $ 3 $ -rd to the $ 3 $ -rd element.
In the second example, the only subarray which is not good is the subarray from the $ 3 $ -rd element to the $ 4 $ -th element.