#include <stdio.h>
main()
{
	int mark;
	printf("Enter mark: ");
	scanf("%d",&mark);                                                                                                                                                                                                                                                                                                             
	if (mark>80 &&(mark<100))
	{
	 	printf("Very good\n");
    }
    else
    {
	 printf("So bad");
    }
    printf("Design by aphaphat");
}