Cod sursa(job #1553230)
Utilizator | Data | 19 decembrie 2015 14:10:26 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.34 kb |
#include <fstream>
using namespace std;
int i, n, j;
char v[2000001];
int main () {
ifstream fin ("ciur.in");
ofstream fout("ciur.out");
int p=0;
fin>>n;
for(i=2;i<=n;i++)
if(v[i]==0){
p++;
for(j=2*i;j<=n;j+=i)
v[j]=1;
}
fout<<p;
return 0;
}