Cod sursa(job #1340102)
Utilizator | Data | 11 februarie 2015 15:29:04 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 60 |
Compilator | cpp | Status | done |
Runda | 9neplace | Marime | 0.33 kb |
#include <fstream>
using namespace std;
ifstream fin("ciur.in");
ofstream fout("ciur.out");
int main()
{
bool ciur[2000005];
int n, cnt=0;
fin>>n;
for(int i=2; i<=n; i++){
if(ciur[i]==0)
cnt++;
for(int j=i+i; j<=n; j=j+i)
ciur[j]=1;
}
fout<<cnt;
return 0;
}