C Program to check number is prime or not using call by reference


In this program, You will learn how to check number is prime or not using call by reference in c.


Call by Reference

void check(int n, int *p){
    statement
}

Example: How to check number is prime or not using call by reference in c.

#include<stdio.h>

void check(int n, int *p) {
    int i;
    for (i = 2; i < n; i++) {
        if (n % i == 0) {
            *p = 0;
        }
    }
}

int main() {

    int n, p = 1;
    printf("Enter a number:");
    scanf("%d", &n);

    check(n, &p);

    if (p == 1) {
        printf("Number is prime:%d", n);
    } else {
        printf("Number is not prime:%d", n);
    }

    return 0;
}

Output:

Enter a number:17                                                                                                                      
Number is prime:17