#include <stdio.h>
/* dato un numero < 30 dire se sia primo */
int main(void) {int n, primo[11]={1,2,3,5,7,11,13,17,19,23,29}, pr=0, fr=0;
scanf("%d", &n
); // legge n if (n
<0 || n
>30) { printf("Numero fuori range"); fr
=1; } else {
if (n==primo[0]) pr=1; if (n==primo[1]) pr=1;
if (n==primo[2]) pr=1; if (n==primo[3]) pr=1;
if (n==primo[4]) pr=1; if (n==primo[5]) pr=1;
if (n==primo[6]) pr=1; if (n==primo[7]) pr=1;
if (n==primo[8]) pr=1; if (n==primo[9]) pr=1;
if (n==primo[10]) pr=1; }
if (pr
==1 && !fr
) printf ("Il numero %d e' primo",n
); if (pr
==0 && !fr
) printf ("Il numero %d non e' primo",n
); return 0;
}
// L'esercizio e' un esempio di soluzione senza l'uso del ciclo
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