Cod sursa(job #158551)

Utilizator redkar23Dezactiveazama redkar23 Data 13 martie 2008 18:08:33
Problema Ciurul lui Eratosthenes Scor 100
Compilator c Status done
Runda Arhiva educationala Marime 0.33 kb
Raporteaza aceasta sursa 
#include <stdio.h>
#include <math.h>
#define max 2000002

char v[max];
long n,count,i,j;

FILE *f,*g;

int main(){

f=fopen("ciur.in","r");
g=fopen("ciur.out","w");

fscanf(f,"%ld",&n);

for(i=3;i<=n;i+=2)
   if(!v[i]&&i%2) {
    count++;
    for(j=3*i;j<=n;j+=2*i)  v[j]=1; 
   } 

fprintf(g,"%ld\n",count+1);
fclose(g);
return 0;
}