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: Wrong Answer)

import java.util.*;

class Main 
{
	static boolean odd[] = new boolean[100001];

	static void countOdd()
	{
		for(int i = 2; i < 100001; i++)
			odd[i] = false;

		for(int i = 2; i < 100001; i++)
		{
			boolean flag = true;
			for(int j = 2; j < i / 2; j++)
				if(i % j == 0)
				{
					flag = false;
					break;
				}
			
			if(flag)
				odd[i] = true;
		}
	}

  	public static void main(String[] args) 
	{
		countOdd();
    	Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();

		for(int i  = 0; i < n; i++)
		{
			int x = sc.nextInt(),
				y = sc.nextInt(),
				count = 0;

			for(int j = x; j <= y; j++)
				if(odd[j] && odd[(j + 1) / 2])
					count++;

			System.out.println(count);
		}	
  	}
}