#include <stdio.h>

int main() {

  int n, number = 0, selection, prime = 1;

  while ( 1 ) {

    printf( "(1) Enter a Number\n" );
    printf( "(2) Is %d Prime?\n", number );
    printf( "(3) Quit\n" );
    printf( "Enter a Selection:  " );
    scanf( "%d", &selection );
    printf( "\n" );

    if ( selection == 1 ) {
      printf( "Enter the Number:  " );
        scanf( "%d", &number );
    }

    else if ( selection == 2 ) {
      if ( number > 0 ) {
        prime = 1;

        for ( n = 2; n < number; n++ ) {
          if ( number % n == 0 ) {
            printf( "%d is not prime, it is divisible by %d\n", number, n );
            prime = 0;
            // break;
          }
        }

        // if ( n == number ) {
        if ( prime ) {
          printf( "%d is a prime number\n", number );
        }
      }
      else {
        printf(" Please Enter a Number First\n" );
      }
    } // closes else if ( selection == 2 )

    else if ( selection == 3 ) {
      printf( "Goodbye.\n" );
      break;
    }
  } // closes the while( 1 )

  return 0;
}