Cod sursa(job #1366881)
Utilizator | Data | 1 martie 2015 14:25:02 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.35 kb |
#include <fstream>
#include <bitset>
using namespace std;
ifstream in("ciur.in");
ofstream out("ciur.out");
bitset <2000001> v;
int main()
{
int nr=1,i,n,j;
in>>n;
for(i=3;i<=n;i+=2)
if(v[i]==0)
{
for(j=2*i;j<=n;j+=i)
v[j]=1;
nr++;
}
out<<nr;
return 0;
}