Cod sursa(job #1206935)
Utilizator | Vilau Marian marian.vilau | Data | 11 iulie 2014 15:46:09 |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.34 kb |
#include <fstream>
#include <algorithm>
using namespace std;
long long n,nrp,i,j;
bool w[2000005];
int main()
{
ifstream f("ciur.in");
ofstream g("ciur.out");
w[1]=true;
f>>n;
for(i=2;i<=n;i++)
if(w[i]==false)
{
nrp++;
for(j=i*i;j<=n;j=j+i) w[j]=true;
}
g<<nrp;
return 0;
}