Cod sursa(job #2104245)
Utilizator | Data | 11 ianuarie 2018 14:46:39 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.33 kb |
#include<fstream>
using namespace std;
ifstream fin("ciur.in");
ofstream fout("ciur.out");
int N,Sol;
bool A[2000005];
void Ciur()
{
for(int i=2;i<=N;i++)
if(A[i]==0)
{
for(int j=2*i;j<=N;j+=i)
A[j]=1;
Sol++;
}
}
int main()
{
fin>>N;
Ciur();
fout<<Sol;
}