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

void swap(long* p, long* q)
{
  long t = *p;
  *p = *q;
  *q = t;
}

long course1 = 15213;
long course2 = 18243;

void call_swap() {
  swap(&course1, &course2);
}

void swap_a(long *xp, long *yp) {
  volatile long loc[2];
  loc[0] = *xp;
  loc[1] = *yp;
  *xp = loc[1];
  *yp = loc[0];
}

long scount = 0;

/* Swap a[i] and a[i+1] */
void swap_ele_se(long a[], int i) {
  swap(&a[i], &a[i+1]);
  scount++;
}

/* Swap a[i] and a[i+1] */
void swap_ele(long a[], int i) {
  swap(&a[i], &a[i+1]);
}

long sum = 0;
/* Swap a[i] and a[i+1] */
void swap_ele_su(long a[], int i) {
  swap(&a[i], &a[i+1]);
  sum += (a[i] * a[i+1]);
}


int main() { 
  printf("Initially: course1 = %ld, course2 = %ld\n", course1, course2);
  call_swap();
  printf("Finally: course1 = %ld, course2 = %ld\n", course1, course2);
  return 0;
}