Cod sursa(job #1324504)
Utilizator | Data | 22 ianuarie 2015 14:39:30 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.42 kb |
#include<fstream>
#include<iostream>
using namespace std;
ifstream fin("ciur.in");
ofstream fout("ciur.out");
bool v[2000001];
int n,i,s,smax,stm,drm,st,dr,j,nr;
int main ()
{
fin>>n;nr=0;
v[0]=true;
v[1]=true;
for(i=2;i<=n;i++)
{
if(v[i]==false)
{
nr++;
for(j=2;i*j<=n;j++)
v[i*j]=true;
}
}
fout<<nr;
return 0;
}