4.3BSD-UWisc/lib/learn/C/L32.1a

#print
Write a program
   pair(a,b)
which accepts as arguments two pointers to integers
and swaps the integers if necessary so that the
first argument points to the larger one; that is
	int x,y;
	x = 9;
	y = 15;
	pair( &x, &y);
results in x being 15 and y 9.  Leave the program
on file "pair.c"; compile, test it, and type "ready".
#once #create tzaqc.c
main()
{
	int x,y;

	y=200;
	x = 0;
	pair(&y, &x);
	if (x != 0 || y != 200) 
		return(1);
	pair(&x,&y);
	if (x != 200 || y != 0) 
		return(1);
	x = 30;
	y = 23097;
	pair(&x,&y);
	if (x != 23097 || y !=  30) 
		return(1);
	return(0);
}
#user
cc tzaqc.c pair.o
a.out 
#succeed
pair(a, b)
int *a, *b;
{
	int t;

	if (*a <= *b) {
		t = *a;
		*a = *b;
		*b = t;
	}
}
#log
#next
33.1a 10