Cod sursa(job #655205)
Utilizator | Data | 1 ianuarie 2012 19:19:43 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 40 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.31 kb |
#include <fstream>
using namespace std;
int main ()
{
ifstream in ("ciur.in");
ofstream out ("ciur.out");
bool prim[1000000]={0};
int j=0, e;
in>>e;
prim[0]=1;
prim[1]=1;
for(int i=2;i<=e;i++){
if(prim[i]==0){
j++;
for(int j=i+i; j<=e; j+=i)
prim[j]=1;}}
out<<j;
return 0;
}