prime number algorithm in c code example

Example 1: prime number c program

int isPrime(int n) {
  for (int i = 2; i < n; i++) if (n % i == 0) return 0; 
  return 1;
}

Example 2: prime number c

#include <stdio.h>
int main()
{
   int i, num, p = 0;
   printf("Please enter a number: \n");
   scanf("%d", &num);
   for(i=1; i<=num; i++)
   {
      if(num%i==0)
      {
         p++;
      }
   }
   if(p==2)
   {
      printf("Entered number is %d "\
             "and it is a prime number.",num);
   }
   else
   {
      printf("Entered number is %d "\
             "and it is not a prime number.",num);
   }
}