Problem:
Score : 400 points

Problem Statement

We say that a odd number N is similar to 2017 when both N and (N+1)/2 are prime.

You are given Q queries.

In the i-th query, given two odd numbers l_i and r_i, find the number of odd numbers x similar to 2017 such that l_i ≤ x ≤ r_i.

Constraints

1≤Q≤10^5

1≤l_i≤r_i≤10^5

l_i and r_i are odd.

All input values are integers.

Input

Input is given from Standard Input in the following format:

Q
l_1 r_1
:
l_Q r_Q

Output

Print Q lines. The i-th line (1≤i≤Q) should contain the response to the i-th query.

Sample Input 1

1
3 7

Sample Output 1

2

3 is similar to 2017, since both 3 and (3+1)/2=2 are prime.

5 is similar to 2017, since both 5 and (5+1)/2=3 are prime.

7 is not similar to 2017, since (7+1)/2=4 is not prime, although 7 is prime.

Thus, the response to the first query should be 2.

Sample Input 2

4
13 13
7 11
7 11
2017 2017

Sample Output 2

1
0
0
1

Note that 2017 is also similar to 2017.

Sample Input 3

6
1 53
13 91
37 55
19 51
73 91
13 49

Sample Output 3

4
4
1
1
1
2

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Time Limit Exceeded)

import java.util.*;
public class Main {
	public static void main(String[] args){
		Scanner sc=new Scanner(System.in);
		ArrayList<Integer> x=new ArrayList<>();
		x.add(2);x.add(3);
		for(int i=5;i<=100000;i+=2){
			boolean can = true;
			for(int k=2;k<=i/2;k++){
				if(i%k==0){
					can = false;
					break;
				}
			}
			if(can)
				x.add(i);
		}
		int n=sc.nextInt();
		while(n-->0){
			int sum = 0;
			int a=sc.nextInt(),b=sc.nextInt();
			for(int i=a;i<=b;i+=2){
				if(x.contains(i)&&x.contains((i+1)/2)){
					sum++;
				}
			}
			System.out.println(sum);
		}
	}
}