Cod sursa(job #2380750)
Utilizator | Data | 15 martie 2019 14:44:39 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 0 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva educationala | Marime | 0.39 kb |
#include <fstream>
#include <algorithm>
using namespace std;
ifstream cin ("ciur.in");
ofstream cout ("ciur.out");
bool v[2000001];
int main()
{
int n,i,j,x,k,cnt=0;
cin>>n;
for (i=3; i<=n; i+=2)
{
if (v[i]==0)
{
for (j=i*2; j<=n; j+=i)
v[j]=1;
}
cnt++;
}
cout<<cnt;
return 0;
}