Cod sursa(job #379367)
Utilizator | Data | 1 ianuarie 2010 12:49:59 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.41 kb |
#include <iostream.h>
#include <fstream.h>
int main()
{
long int n;
int p,c=0;
fstream f("ciur.in",ios::in);
fstream g("ciur.out",ios::out);
bool prim[2000000];
f>>n;
for(int i=2;i<=n;i++)
if(!prim[i])
{
c++;
for(int j=2*i;j<=n;j=j+i)
prim[j]=1;
}
g<<c;
}