Cod sursa(job #1284491)
Utilizator | Data | 6 decembrie 2014 16:05:59 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 20 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.33 kb |
#include <fstream>
using namespace std;
bool prim[2000002];
ifstream f("ciur.in");
ofstream g("ciur.out");
int main()
{int n,j,nr=0,i;
f>>n;
for(i=2;i<=n;i++)
prim[i]=1;
for(i=2;i<=n;i++)
if(prim[i])
{nr++;
for(j=1;j<=n;j++)
prim[i*j]=0;
}
g<<nr;
f.close();
g.close();
return 0;
}