Cod sursa(job #1541679)
Utilizator | Data | 4 decembrie 2015 14:50:24 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.35 kb |
#include <fstream>
using namespace std;
ifstream in("ciur.in");
ofstream out("ciur.out");
bool v[2000001];
int gg;
int main()
{
int n,i,j;
in>>n;
for(i=2;i<=n;i++){
if(v[i]==0){
gg++;
for(j=i*2;j<=n;j+=i){
v[j]=1;
}
}
}
out<<gg;
return 0;
}