Cod sursa(job #368189)
Utilizator | Data | 24 noiembrie 2009 08:26:50 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 30 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.41 kb |
#include <stdio.h>
#include <math.h>
int n,s,ri,i,j;
char p;
int main(){
FILE *f = fopen("ciur.in","r");
fscanf(f,"%d",&n);
fclose(f);
s = 0;
for (i=2;i<=n;i++) {
p = 1;
ri = (int)sqrt(i);
for (j=2;j<=i/2;j++)
if (i%j == 0) {
p = 0;
break;
}
if (p==1)
s++;
}
FILE *g = fopen("ciur.out","w");
fprintf(g,"%d",s);
fclose(g);
return 0;
}