Cod sursa(job #1808005)
Utilizator | Data | 17 noiembrie 2016 10:30:41 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.34 kb |
#include <fstream>
#include <iostream>
using namespace std;
int v[2000005];
ifstream in("ciur.in");
ofstream out("ciur.out");
int main()
{
int n,cnt=0;
in>>n;
for(int i=2;i*i<=n;i++)
if(v[i]==0)
{
cnt++;
for(int j=2*i;j+i<=n;j=j+i)
v[j]=1;
}
out<<cnt;
}