Cod sursa(job #1815472)
Utilizator | Data | 25 noiembrie 2016 11:55:14 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.4 kb |
#include <fstream>
using namespace std;
ofstream fout("ciur.out");
ifstream fin("ciur.in");
int n,i,j,nr;
bool c[2000010];
int main()
{
fin>>n;
c[0]=c[1]=1;
for(i=2;i<=n;i++)
{
if(c[i]==0)
{
nr++;
for(j=i;j<=n;j+=i)
{
c[j]=1;
}
}
}
fout<<nr;
return 0;
}