Cod sursa(job #305632)
Utilizator | Data | 17 aprilie 2009 22:51:42 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 20 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.32 kb |
#include<fstream.h>
long int n,prim[10000],i,j,nr,contor;
int main()
{
ifstream in("ciur.in");
ofstream out("ciur.out");
in>>n;
for(i=2;i<=n;i=i+1)
prim[i]=1;
for(i=2;i<=n;i=i+1)
if(prim[i]==1)
{for(j=i+i;j<=n;j=j+i)
prim[j]=0;
contor=contor+1;
}
out<<contor;
in.close();
out.close();
return 0;
}