Cod sursa(job #928682)
Utilizator | Data | 26 martie 2013 17:03:43 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.35 kb |
#include <fstream>
using namespace std;
int n,nr,i,j,p;
bool ok[2000000];
int main()
{ifstream f("ciur.in");
ofstream g("ciur.out");
f>>n;
nr=1;
for (i=2;i<=n; i++) ok[i]=true;
for (i=2; i<=n; i++)
if (ok[i]==true) {
p++;
for (j = 2*i; j <= n; j += i)
ok[j] = false;
}
g<<p;
return 0;
}