Problem
https://projecteuler.net/problem=10
The sum of the primes below 10 is 2 + 3 + 5 + 7 = 17.
Find the sum of all the primes below two million.
Answer: 142913828922
Solution
#include <iostream>
#include "sieve_eratos.h"
using namespace std;
int main(int argc, char* argv[] )
{
CSieveOfEratosthenes* cs = new CSieveOfEratosthenes(20000000);
cout << "Answer: " << cs->sum(2000000) << endl;
}The sum method:
uint64_t sum(int a_max)
{
uint64_t total = 0;
size_t i;
for( i = 0; i < a_max ; i++){
if( true == (*m_primes)[i]){
total += i;
}
}
return total;
}