Cod sursa(job #688148)
Utilizator | Data | 23 februarie 2012 08:48:51 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.29 kb |
#include <fstream>
#include <bitset>
using namespace std;
int main ()
{
ifstream in ("ciur.in");
ofstream out ("ciur.out");
bitset <2000000> v;
int i, j=0, n;
in>>n;
for(i=3; i<=n; i+=2){
if(v[i]==0) {
j++;
for(j=i*i; j<=n; j+=2*i)
v[j]=1;}}
out<<j;
return 0;
}