#include <stdio.h>

void swap(int *a, int *b);
void sort(int *x, int *y);

int main(void) {
	int x, y; 
	
	x = 20;
	y = 10;
	
	printf("並べ替え前: x = %d, y = %d\n", x, y);
	
	sort(&x, &y);
	
	printf("並べ替え後: x = %d, y = %d\n", x, y);

	return 0;
}
void swap(int *a, int *b) { 
	int t = *a; 
	*a = *b; 
	*b = t;
}	
void sort(int *x, int *y) { 
	if (*x < *y) { 
	swap(x, y); 
		
	}
}