Cod sursa(job #1058008)
Utilizator | Data | 14 decembrie 2013 22:33:46 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.42 kb |
#include <fstream>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
bool v[2000003];
int main()
{
int i,j,n,c=0;
f>>n;
for(i=2;i<=n;i++)
v[i]=1;
for(i=2;i<=n;i++)
{ if(v[i])
{
c++;
for(j=i+i;j<=n;j+=i)
v[j]=0;
}
}
g<<c;
return 0;
}