Cod sursa(job #1311463)
Utilizator | Data | 8 ianuarie 2015 11:28:30 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.27 kb |
#include <iostream>
using namespace std;
int main() {
bool a[2000001];
int nr=0, n, i, j;
cin>>n;
for (i=2;i<=n;i++)
a[i]=1;
for (i=2;i<=n/2;i++)
if (a[i])
for (j=i;j<=n/i;j++)
a[i*j]=0;
for (i=2;i<=n;i++)
if (a[i]) nr++;
cout<<nr;
return 0;
}