typedef struct node
{
int n;
struct node* next;
}
node;
In the above code there is struct node* next inside the struct node. I don't understand the meaning of it.
4 Answers
In the code there is
struct node* nextinside thestruct node. I don't understand the meaning of it.
Explanation :
A node is a general term used to refer a self referential structure.(click on link to know more)
and going by definition,
A self referential structure is a typical structure whose definition has one or more of its member as a pointer to its own type.
Here in your code next is such a member of the structure struct node which is a pointer to it's own type therefore you see it as a pointer to itself in this manner inside of struct :
struct node* next;
That's the reason why struct keyword is used inside of struct
Purpose of using self referential structures :
self referential structures are very much helpful in building data structures such a linked lists... and in fact the variable next is the very member which is useful in making links between nodes in a linked list :)
Comments
struct node* (note the *) is a pointer (*) to a struct node. That means that one node can connect to another, via the pointer, without including the other.
This is referred to as a "linked list" structure. I found a Stanford University tutorial that looks like it covers the subject fairly thoroughly.
Comments
In simple words, it means that next would also be of the same structure as that of node. So next will also have a field int n and another next.. Also this is dynamic so you don't have to allocate any memory before hand.. you can keep on adding as many node as you want ( you still have to assign memory to each node though -- search for how to use malloc to allocate memory to struct node ) And as it is of pointer type ( struct node* next ) it means you can store the address of your next node in to it and link nodes.. See the linked list implementation for better understanding.. I hope it helps :)
Comments
Answering the title: In C, all non-standard types need to be prefaced with the struct keyword:
#include <stdint.h>
typedef uint8_t u8;
typedef uint32_t u32;
struct memory_arena {
size_t size;
u8 *base;
size_t used;
u32 _savePointCount;
size_t _savePoints[8];
};
struct application_state {
#if 1
struct memory_arena globalArena; //<---
#else
memory_arena globalArena; //Valid C++
#endif
};
If it were in C-style C++, you might find this mixed and matched because it's not required.
struct nodeis a type name. That's it.