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Time Limit: 1 s Memory Limit: 128 MB Total points: 100

#467. 配对统计

Statistics

给定 $n$ 个数 $a_1,\cdots,a_n$。

对于一组配对 $(x,y)$,若对于所有的 $i=1,2,\cdots,n$,满足 $|a_x-a_y|\le|a_x-a_i|(i\not=x)$,则称 $(x,y)$ 为一组好的配对($|x|$ 表示 $x$ 的绝对值)。

给出若干询问,每次询问区间 $[l,r]$ 中含有多少组好的配对。

即,取 $x,y$($l\le x,y\le r$ 且 $x\not=y$),问有多少组 $(x,y)$ 是好的配对。

输入格式

第一行两个正整数 $n,m$。

第二行 $n$ 个数 $a_1,\cdots,a_n$。

接下来 $m$ 行,每行给出两个数 $l,r$。

输出格式

$Ans_i$ 表示第 $i$ 次询问的答案,输出 $\sum_{i=1}^m\limits Ans_i\times i$ 即可。

样例数据

样例 1 输入

3 2
2 1 3
1 2
1 3

样例 1 输出

10

子任务

对于 $20\%$ 的数据,$n,m \leq 300$

对于 $40\%$ 的数据,$n,m \leq 5\,000$

对于 $70\%$ 的数据,$n,m \leq 50\,000$

对于 $100\%$ 的数据,$1 \leq n,m \leq 3 \times 10^5$,$1 \leq a_i \leq 10^9$,$1 \leq l \leq r \leq n$,$a_i \ne a_j$ 对所有 $i \ne j$

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