Cod sursa(job #1275730)
Utilizator | Data | 25 noiembrie 2014 15:14:39 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.27 kb |
#include <iostream>
#include <fstream>
using namespace std;
ifstream in("ciur.in");
ofstream out("ciur.out");
bool v[2000001];
int main()
{int n,i,j,nr=0;
in>>n;
for(i=2;i<=n;i++)
{if(v[i]==0){nr++;
for(j=2*i;j<=n;j+=i)
v[j]=1;
}
}
out<<nr;
}