Problem Description Life is a game,and you lose it,so you suicide.
But you can not kill yourself before you solve this problem:
Given you a sequence of number a
1, a
2, ..., a
n.They are also a permutation of 1...n.
You need to answer some queries,each with the following format:
If we chose two number a,b (shouldn't be the same) from interval [l, r],what is the maximum gcd(a, b)? If there's no way to choose two distinct number(l=r) then the answer is zero.
Input First line contains a number T(T <= 5),denote the number of test cases.
Then follow T test cases.
For each test cases,the first line contains a number n(1 <= n <= 50000).
The second line contains n number a
1, a
2, ..., a
n.
The third line contains a number Q(1 <= Q <= 50000) denoting the number of queries.
Then Q lines follows,each lines contains two integer l, r(1 <= l <= r <= n),denote a query.
Output For each test cases,for each query print the answer in one line.
Sample Input
1
10
8 2 4 9 5 7 10 6 1 3
5
2 10
2 4
6 9
1 4
7 10
Sample Output
5
2
2
4
3
Author WJMZBMR
Source 2013 Multi-University Training Contest 3
题意： 求区间内的两两gcd里最大的
思路： 我们可以对于每个数求出因子，而在一个区间内出现超过两次的那么必然是一个gcd,这样我们只需要把所有出现超过两次的因子加入线段树中，并更新即可 对于查询，我们可以先按r从小到大排序，离线处理所有答案
#include
#include
#include
#include
#include
#include
#include