Cod sursa(job #301128)

Utilizator alexysPop Carla alexys Data 7 aprilie 2009 22:38:39
Problema Ciurul lui Eratosthenes Scor 20
Compilator cpp Status done
Runda Arhiva educationala Marime 0.35 kb
Raporteaza aceasta sursa 
#include<iostream>
#include<fstream>
using namespace std;
long n,contor,i,j;
char p[20005];
ifstream f("ciur.in");
ofstream g("ciur.out");
int main()
{f>>n;
p[1]=0;
for(i=2; i<=n; i++)
p[i]=1;
for(i=2; i<=n; i++)
if(p[i])
for(j=i+i; j<=n; j=j+i)
p[j]=0;
for(i=1;i<=n;i++)  
if(p[i]) contor++;  
        
g<<contor<<endl;
return 0;
}