Cod sursa(job #872512)
Utilizator | Data | 6 februarie 2013 09:49:42 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.29 kb |
#include<iostream>
#include<cstdio>
using namespace std;
bool v[2000001];
int main()
{
int n,d,i,s=1,nr=0;
freopen("ciur.in","r",stdin);freopen("ciur.out","w",stdout);
cin>>n;
for(d=3;d<=n;d+=2)
{
if(!v[d])
{
for(i=d+d;i<=n;i+=d)
v[i]=1;
++s;
}
}
cout<<s;
}