Cod sursa(job #411261)
Utilizator | Data | 4 martie 2010 19:54:20 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 30 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.35 kb |
#include<fstream>
using namespace std;
int prim(long long nr)
{
for(int i=2;i*i<=nr;++i) if(nr%i==0) return 0;
return 1;
}
int main()
{
long long n,s=0;
ifstream fi("ciur.in");
ofstream fo("ciur.out");
fi>>n;
for(int i=2;i<=n;++i) if(prim(i)) ++s;
fo<<s;
fi.close();
fo.close();
return 0;
}