Codeforces J. Soldier and Number Game（素数筛）

题目描述：

Soldier and Number Game

time limit per test

3 seconds

memory limit per test

256 megabytes

input

standard input

output

standard output

Two soldiers are playing a game. At the beginning first of them chooses a positive integer n and gives it to the second soldier. Then the second one tries to make maximum possible number of rounds. Each round consists of choosing a positive integer x > 1, such that n is divisible by x and replacing n with n / x. When n becomes equal to 1 and there is no more possible valid moves the game is over and the score of the second soldier is equal to the number of rounds he performed.

To make the game more interesting, first soldier chooses n of form a! / b! for some positive integer a and b (a ≥ b). Here by k! we denote the factorial of k that is defined as a product of all positive integers not large than k.

What is the maximum possible score of the second soldier?

Input

First line of input consists of single integer t (1 ≤ t ≤ 1 000 000) denoting number of games soldiers play.

Then follow t lines, each contains pair of integers a and b (1 ≤ b ≤ a ≤ 5 000 000) defining the value of n for a game.

Output

For each game output a maximum score that the second soldier can get.

Examples

Input

Copy

23 16 3


Output

Copy

25


代码：

#include <iostream>
#include <cstdio>
#include <memory.h>
#include <ctime>
#define max_n 5000005
using namespace std;
int t;
long long a,b;
int prime[max_n];
int num[max_n];
template<typename T>
{
x=0;int f=0;char ch=getchar();
while('0'>ch||ch>'9'){if(ch=='-')f=1;ch=getchar();}
while('0'<=ch&&ch<='9'){x=10*x+ch-'0';ch=getchar();}
x=f?-x:x;
}
void init()
{
memset(num,0,sizeof(num));
memset(prime,-1,sizeof(prime));
prime[0] = prime[1] = 0;
for(int i = 2;i<=max_n;i++)
{
if(prime[i]==-1)
{
num[i]++;
for(int j = 2*i;j<=max_n;j+=i)
{
prime[j] = 0;
int tmp = j;
while(tmp%i==0)
{
num[j]++;
tmp/=i;
}

}
}
}
for(int i = 2;i<=max_n;i++)
{
num[i]+=num[i-1];
}
}
#pragma optimize(2)
int main()
{
//clock_t start = clock();
init();
//clock_t end = clock();
//printf("%f s\n",(double)(end-start)/CLOCKS_PER_SEC);