Cod sursa(job #1641163)
Utilizator | Data | 8 martie 2016 21:19:55 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 30 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.29 kb |
#include <fstream>
using namespace std;
ifstream fin ("ciur.in");
ofstream fout ("ciur.out");
int n,i,c,j,v[2000001];
int main() {
fin>>n;
for(i=2;i<=n;i++)
if(v[i]==0){
c++;
for(j=i+i;j<=n;j+=i)
v[j]=1;
}
fout<<c;
}