function is prime C code example

Example 1: c program to check prime number using for loop

#include <stdio.h>
int main() {
    int n, i, flag = 0;
    printf("Enter a positive integer: ");
    scanf("%d", &n);

    for (i = 2; i <= n / 2; ++i) {

        // condition for non-prime
        if (n % i == 0) {
            flag = 1;
            break;
        }
    }

    if (n == 1) {
        printf("1 is neither prime nor composite.");
    }
    else {
        if (flag == 0)
            printf("%d is a prime number.", n);
        else
            printf("%d is not a prime number.", n);
    }

    return 0;
}

Example 2: prime factorization in c

#include <stdio.h>
#define MIN 100
#define MAX 100000


int main(){
    int pdiv=2,j;
    for (int num=MIN;num<=MAX;num++){
        printf("The prime factors of %d are:\n",num);
        j=num;
        do {
            
            if (j%pdiv==0)
            {
                
                printf("%d\n",pdiv);
                j=j/pdiv;
            }else
            {
               pdiv++; 
            }
            
            
        }while(j>1);
        pdiv=2;
        
    }



}