P4005 [CF1485B] Replace and Keep Sorted
普及-
题目描述

Given a positive integer $k$, two arrays are called $k$-similar if:

  • they are strictly increasing;
  • they have the same length;
  • all their elements are positive integers between $1$ and $k$ (inclusive);
  • they differ in exactly one position.

You are given an integer $k$, a strictly increasing array $a$ and $q$ queries. For each query, you are given two integers $l_i \leq r_i$. Your task is to find how many arrays $b$ exist, such that $b$ is $k$-similar to array $[a_{l_i},a_{l_i+1}\ldots,a_{r_i}]$.

Input

The first line contains three integers $n$, $q$ and $k$ ($1\leq n, q \leq 10^5$, $n\leq k \leq 10^9$) — the length of array $a$, the number of queries and number $k$.

The second line contains $n$ integers $a_1, a_2, \ldots,a_n$ ($1 \leq a_i \leq k$). This array is strictly increasing  — $a_1 < a_2 < \ldots < a_n$.

Each of the following $q$ lines contains two integers $l_i$, $r_i$ ($1 \leq l_i \leq r_i \leq n$).

Output

Print $q$ lines. The $i$-th of them should contain the answer to the $i$-th query.

输入格式

见题面 Input 部分

输出格式

见题面 Output 部分

样例输入
4 2 5 1 2 4 5 2 3 3 4
样例输出
4 3
提示

In the first example:

In the first query there are $4$ arrays that are $5$-similar to $[2,4]$: $[1,4],[3,4],[2,3],[2,5]$.

In the second query there are $3$ arrays that are $5$-similar to $[4,5]$: $[1,5],[2,5],[3,5]$.