#include<stdio.h>
int main(void)
{
	int x,y,a,b,c,d;
	x=1;
	y=2;
	a=x+y;
	b=x-y;
	c=x*y;
	d=x/y;
	printf("a=%d\n",a);
	printf("b=%d\n",b);
	printf("c=%d\n",c);
	printf("d=%d\n",d);
	
	return 0; 
}