Cod sursa(job #1348280)
Utilizator | Data | 19 februarie 2015 16:55:19 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.34 kb |
#include <fstream>
using namespace std;
ifstream in("ciur.in");
ofstream out("ciur.out");
bool v[2000002];
int main()
{
int n,i,j,cont=0;
in>>n;
for(i=2;i<=n;++i)
if(v[i]==0)
{
++cont;
for (j=i+i;j<=n;j=j+i)
v[j]=1;
}
out<<cont;
return 0;
}