#include<stdio.h>

 struct xy {
 int x;
 int y;
 };

 struct zw {
 int z;
 struct xy w;
 };

 int main(void)
 {
 struct zw a;
 struct zw b={10,{20,30}};
 struct zw c={40,{50,60}};

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

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

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

 a=c;
 printf("a.z = %d\n",a.z);
 printf("a.w.x =%d\n", a.w.x);
 printf("a.w.y =%d\n", a.w.y);

 return 0;
 }