int is_prime_number(int n) { if (n < 0) { // treat neg. inputs as their positive counterparts n *= -1; } if (n == 1) { // 1 is a special case return 0; } // for all other cases return check_if_prime(n, 2); }
int check_if_prime(int n, int m) { if (m == n) { // base case: all factors tested, n is prime return 1; } if (n % m == 0) { // base case: n divisible by m, n is not prime return 0; } // else: n is not divisible by m, but there are other factors to test; call again return check_if_prime(n, m + 1); }
int is_prime_number(int n) { if (n < 0) { n *= -1; } if (n == 1) { return 0; } //else return check_if_prime(n, n/2); }
int main(){ int extra; char *len = "prime"; int num; int is_prime,i; for(i = 0;i < 10;i++){printf("Introduceti numar:"); scanf("%d", &num); is_prime = check_if_prime(num); if(is_prime) printf("is %s\n",len); else printf("is not %s\n",len); extra = get_sum(num); printf("sum (1..%d) is %d\n",num,extra); } return 0; }
int check_m_by_p(int n, int m, int p) { //printf("checking m by p, m is %d, p is %d\n", m, p); if (p == 1) { return check_if_prime (n, m - 1); } // else if (n / m == p) { //printf("checking m by p\n"); if (m * p == n) { return 0; } } // ELSE return check_m_by_p(n, m, p - 1); }
void main(void) { int i = 2; int count = 0; int array[WHICHPRIME]; while (count < WHICHPRIME) { if (check_if_prime(i) == 0) { printf("%d is a prime number.\n",i); count++; array[count] = i; } else printf("%d is not a prime number.\n",i); i++; } printf("Prime #%d is %d.\n",WHICHPRIME,array[count]); // printf("Prime #%d between 1 and %d is %d.\n",WHICHPRIME,TOTAL,array[WHICHPRIME]); }