Cod sursa(job #568445)
| Utilizator |  Iorga Andreea andreea29 |
Data | 31 martie 2011 10:59:17 |
|---|---|---|---|
| Problema | Ciurul lui Eratosthenes | Scor | 0 |
| Compilator | cpp | Status | done |
| Runda | Arhiva educationala | Marime | 0.33 kb |
#include<fstream>
using namespace std;
bool a[2000000001];
int main()
{long int n, i, j;
int nrp;
ifstream f("ciur.in");
ofstream h("ciur.out");
f>>n;
nrp=0;
a[1]=1;
for (i=2; i<=n; i++)
if (a[i]==0)
{nrp=nrp+1;
j=2*i;
do
{a[j]=1;
j=j+i;}
while (j<=n);}
h<<nrp<<endl;
f.close();
h.close();
return 0;
}