Cod sursa(job #1963080)
Utilizator | Data | 12 aprilie 2017 11:47:00 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.35 kb |
#include <fstream>
using namespace std;
ifstream cin("ciur.in");
ofstream cout("ciur.out");
bool v[2000005]={0};
int n,i,j,c=0;
int main()
{
cin>>n;
for(i=2;i<=n;i++)
{
if(v[i]==0)
{
c++;
for(j=1;j*i<=n;j++)
v[i*j]=1;
}
}
cout<<c;
return 0;
}