// ex_ch9_5.c
#include <stdio.h>

void larger_of(double * first, double * second);

int main(void)
{
	double x = 4.0, y = 7.0;
	
	printf("Original x = %.2f and y = %.2f.\n",
	       x, y);
	larger_of(&x, &y);
	printf("New x = %.2f and y = %.2f.\n",
	       x, y);
	return 0;
}

void larger_of(double * first, double * second)
{
	if (*first < *second)
		*first = *second;
	else
		*second = *first;
}