问题 F: Product of Sorting Powers
内存限制：512 MB
时间限制：15 S
题面：传统
评测方式：文本比较
上传者：
提交：2
通过：1
题目描述
Given a sequence A of length n.
There are m queries, each given l, r, let B1,B2,…,Br−l+1 as the result of sorting A_rAl,Al+1,…,Ar, calculate:
输入格式
The first line of the
input contains two integers n,
m (1≤n≤10^6, 1≤m≤5000) - the length of A and the number
of queries.
The second line contains n integers A1,A2,…,An (1≤Ai≤10^9).
Each of the following m lines contains two
integers l,
r (1≤l≤r≤n).
输出格式
For each query, print a single integer - the answer of the query, modulo 10^9+7.
输入样例 复制
6 5
8 2 5 9 7 7
1 4
2 6
1 3
3 6
2 5输出样例 复制
588255953
426219106
12500000
575819351
16793812