codeforces Problem- 630K Indivisibility

K. Indivisibility
time limit per test
0.5 seconds
memory limit per test
64 megabytes
input
standard input
output
standard output

IT City company developing computer games decided to upgrade its way to reward its employees. Now it looks the following way. After a new game release users start buying it actively, and the company tracks the number of sales with precision to each transaction. Every time when the next number of sales is not divisible by any number from 2 to 10 every developer of this game gets a small bonus.

A game designer Petya knows that the company is just about to release a new game that was partly developed by him. On the basis of his experience he predicts that n people will buy the game during the first month. Now Petya wants to determine how many times he will get the bonus. Help him to know it.

Input

The only line of the input contains one integer n (1 ≤ n ≤ 1018) — the prediction on the number of people who will buy the game.

Output

Output one integer showing how many numbers from 1 to n are not divisible by any number from 2 to 10.

Examples
input
12
output
2



//容斥原理 
#include <cstdio>
#define LL __int64
int one[]={2,3,5,7};
int two[]={6,10,14,15,21,35};
int three[]={30,42,70,105};
int main()
{
	LL n;
	while(~scanf("%I64d",&n))
	{
		LL sum=0;
		for(int i=0;i<4;++i)
		{
			sum+=n/one[i];
		}
		for(int i=0;i<6;++i)
		{
			sum-=n/two[i];
		}
		for(int i=0;i<4;++i)
		{
			sum+=n/three[i];
		}
		sum-=n/210;//能被2,3,5,7整除的總和 
		printf("%I64d\n",n-sum);
	} 
	return 0;
}


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