Cod sursa(job #275577)

Utilizator DrakeDemonSebestin Dragos DrakeDemon Data 10 martie 2009 16:00:40
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.34 kb
Raporteaza aceasta sursa 
#include<stdio.h>

int   n,i,j,nr;
char  s[2000005];

int main(){
FILE *f = fopen("ciur.in","r");
FILE *g = fopen("ciur.out","w");
fscanf(f,"%d",&n);
for(i=2;i<=n;i++)
	s[i] = 1;
for(i=2;i<=n;i++){
	if(s[i]){
		nr++;
		for(j=i+i;j<=n;j+=i){
			s[j]=0;
		}
	}
}

fprintf(g,"%d",nr);




fclose(f);
fclose(g) ;
return 0;
}