Cod sursa(job #679535)
Utilizator | Data | 13 februarie 2012 13:46:42 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.29 kb |
#include <fstream>
using namespace std;
long long i,j,n,c;
bool d[2000002];
int main()
{
ifstream f("ciur.in");ofstream g("ciur.out");f>>n; for(i=2;i<=n;i++) d[i]=1; for(i=2;i<=n;i++) d[i]=1;
for(i=2;i<=n;i++) if(d[i]==1) {c++; for(j=i+i;j<=n;j=j+i) d[j]=0;} g<<c;
return 0;
}