How to use a struct inside another struct?

Question

I want to use a nested structure but i dont know how to enter data in it, for example:

struct A {
    int data;
    struct B;
};
struct B {
    int number;
};
         


        

Answer 1

struct A 
{
  int data;
  struct B
  {
    int number;
  }b;
};

int main()
{
  A stage = { 42, {100} };
  assert(stage.data == 42);
  assert(stage.b.number == 100);   
}