C MMI 인터페이스 if_else

#include <stdio.h>

// Needed for exit()
#include <stdlib.h>

void main(void){
int whatToDo = 0;

do{

printf("\n");
printf("1. What time is it?\n");
printf("2. What is todays data?\n");
printf("3. What day is it?\n");
printf("4. Quit\n");

scanf(" %d", &whatToDo);
}while(whatToDo < 1 || whatToDo > 4);

if(whatToDo == 1){
printf("print the time\n");
}else if(whatToDo == 2){
printf("print the date\n");
}else if(whatToDo == 3){
printf("print the day\n");
}else{
printf("Bye Bye\n");
exit(0);
}
}