Cod sursa(job #1402982)
Utilizator | Data | 26 martie 2015 22:39:20 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 30 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.28 kb |
#include <fstream>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
int k=0,i,a[2000000],n,j;
int main()
{
f>>n;
for(i=2;i<=n;i++)
{
if(a[i]==0)
{
for(j=i*2;j<=n;j+=i) a[j]=1;
k++;
}
}
g<<k;
}