Cod sursa(job #2276964)
Utilizator | Data | 5 noiembrie 2018 17:35:59 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva educationala | Marime | 0.33 kb |
#include <fstream>
using namespace std;
int n, i, j, nr;
char f[2000001];
ifstream fin("ciur.in");
ofstream fout("ciur.out");
int main(){
fin>>n;
for(i=2;i<=n;i++)
if(f[i] == 0){
nr++;
for(j=i+i;j<=n;j+=i)
f[j] = 1;
}
fout<<nr;
return 0;
}