Cod sursa(job #308047)
Utilizator | Puscas Sergiu harababurel | Data | 25 aprilie 2009 21:49:37 |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 20 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.56 kb |
#include <iostream>
#include <fstream>
using namespace std;
int main() {
long long n, i, j, v[16000], rez=0;
ifstream f; f.open("ciur.in");
ofstream g; g.open("ciur.out");
f>>n;
rez=0;
for(i=2; i<=n; i++) { v[i]=1; }
for(i=2; i<=n; i++) {
if(v[i]!=0) {
rez++;
for(j=2*i; j<=n; j=j+i) {
v[j]=0;
}
}
}
g<<rez;
f.close();
g.close();
return 0;
}