Cod sursa(job #1200324)
Utilizator | Data | 22 iunie 2014 09:27:50 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 20 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.31 kb |
#include<fstream>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
inline int prim(int x)
{ for(int d=2;d<=x/2;d++)
if(!(x%d)) return 0;
return 1;
}
int main()
{ int n,nr=1,i;
f>>n;
if(n>2)
for(i=3;i<=n;i+=2)
if(prim(i)) nr++;
g<<nr<<"\n";
g.close();
return 0;
}