Cod sursa(job #1913905)
Utilizator | Data | 8 martie 2017 14:38:43 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.32 kb |
#include <iostream>
#include <fstream>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
int i,p,n,j;
bool k[2000001];
int main ()
{
f>>n;
p=0;
for(i=2;i<=n;i++)
{
if(k[i]==0)
{
p++;
for(j=i+i;j<=n;j+=i) k[j]=1;
}
}
g<<p;
return 0;
}