Cod sursa(job #261794)

Utilizator babypink05popescu ioana babypink05 Data 18 februarie 2009 19:31:18
Problema Ciurul lui Eratosthenes Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.3 kb
Raporteaza aceasta sursa 
#include<fstream.h>
#define NM 200000

int main(){

char v[NM+1]={0};
int i,j,n,p;
ifstream fin("ciur.in");
ofstream fout("ciur.out");
fin>>n;
v[1]=1;
for(i=2;i<=n/2;i++)
     if(v[i]==0)
	 for(j=2;i*j<=n;j++)
	      v[i*j]=1;
p=0;
for(i=2;i<=n;i++)   if(v[i]==0) p++;
fout<<p;
 return 0;
}