Cod sursa(job #1976462)
Utilizator | Data | 3 mai 2017 15:08:30 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.31 kb |
#include <fstream>
using namespace std;
ifstream in ("ciur.in");
ofstream out ("ciur.out");
bool ciur[2000001];
int main()
{
int d,i,n,x=0;
in>>n;
for(d=2;d<=n;d++)
if(ciur[d]==0)
{
for(i=d*2;i<=n;i+=d)
ciur[i]=n;
x++;
}
out<<x;
return 0;
}