#include<stdio.h>

 struct a_xy{
 int x;
 int y;
 };

 struct b_xy{
 int x;
 int y;
 };

 int main(void)
 {
 struct a_xy a={10,20};
 struct b_xy b={30,40};

 a.x=b.x;
 printf("a.x = %d\n",a.x);

 //a=b;
 printf("a.y = %d\n",a.y);

return 0;
}