第10問

The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17.

Find the sum of all the primes below two million.

#include <iostream>
#include <math.h>
using namespace std;



long long int prime[1000000];
long long int table[100000000];
int primeCall(){


	int flag=0;
	
	prime[0]=2;
	prime[1]=3;


	for(long long int i=0;i<3000000;i++)
	{
			if(i%2==0)table[i]=0;
			else table[i]=1;
	}

	
	for(long long int p=1;p<1000000;p++)
	{
		if(p%100==0)cout<<prime[p]<<endl;
		for(long long int i=prime[p];i<2001000;i+=2)
		{
			if(i%prime[p]!=0 && flag==0 && table[i]==1)
			{
				prime[p+1]=i;
				flag=1;

			}
			if(i%prime[p]==0)
			{
				table[i]=0;
			}
	
		}


		flag=0;

		if(prime[p+1]>2000000)break;

	}