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  1. #include <stdio.h>
  2. struct Base {
  3.     int num;
  4.     #define DEFAULT_BASE() {.num =1}
  5. };
  6.  
  7. struct DerivedA{
  8.     struct Base base;
  9.     int a;
  10.     #define DEFAULT_DERIVEDA() {DEFAULT_BASE() , .a = 2}
  11. };
  12.  
  13. struct DerivedB{
  14.     struct Base base;
  15.     int b;
  16.     #define DEFAULT_DERIVEDB() {DEFAULT_BASE() , .b = 2}
  17. };
  18.  
  19. struct DerivedA instA = DEFAULT_DERIVEDA();
  20. struct DerivedB instB = { DEFAULT_BASE() , .b = 3 };
  21.  
  22. void func(struct Base * p){
  23.     p->num++;
  24. }
  25.  
  26. void Base_Print(struct Base * obj){
  27. 	printf("num:%d " , obj->num);
  28. }
  29.  
  30. void DeriveA_Print(struct DerivedA * obj){
  31. 	printf("A->");
  32. 	Base_Print(obj);
  33. 	printf(", a:%d\n" , obj->a);
  34. }
  35.  
  36. void DeriveB_Print(struct DerivedB * obj){
  37. 	printf("B->");
  38. 	Base_Print(obj);
  39. 	printf(", b:%d\n" , obj->b);
  40. }
  41.  
  42.  
  43. int main() {
  44.     func(&instA);
  45.     func(&instB);
  46.     DeriveA_Print(&instA);
  47.     DeriveB_Print(&instB);
  48. 	//printf("A->num:%d , a:%d\nB->num:%d , b:%d" , instA.base.num , instA.a , instB.base.num , instB.b );
  49. }
Success #stdin #stdout 0s 4480KB
comments (?)
stdin 
Standard input is empty
stdout 
A->num:2 , a:2
B->num:2 , b:3
https://ideone.com/1fg4hL
language:
C (gcc 8.3)
created:
4 years ago
visibility:
public

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