#include <stdlib.h>
#include <stdio.h>

/* the ranks of academic staff. */

typedef enum { Lecturer, SeniorLecturer, Reader, Professor } Rank;

/* struct giving the rank of a member of staff, together with their
   year of appointment to the rank. In the case of Senior Lecturers,
   their year of appointment as Lecturer is used */

typedef struct {
  Rank rank;
  int year; /* year of appointment */
} staff;

/* Complete this function as specified in the question */

int precedes(staff s1, staff s2) {
  /* BEGIN ANSWER -- do not delete this line */

  // ADD YOUR CODE HERE

  /* END ANSWER -- do not delete this line */
}

int main(void) {
  staff s1 = { Professor, 2010 }; 
  staff s2 = { Lecturer, 1991 };
  printf("Checking that young prof precedes old lecturer: %d\n",
    precedes(s1,s2));
  s2.rank = Professor;
  printf("Checking that young prof is preceded by old prof: %d\n",
    precedes(s1,s2));
  s1.rank = SeniorLecturer; s2.rank = Lecturer;
  s1.year = s2.year = 2000;
  printf("Checking that lect and senior lect are equal: %d\n",
    precedes(s1,s2));
}