Need some help with a C problem. Thanks

1. Solve/ fill in dll header through insertBefore.

2. Call insertBefore & insertAfter in main function

#include "dll.nl struct dllheader makelist struct lnode *makenode ( int val ) void insertFront struct dllheader *L, int val void insertBack struct dllheader *L, int val) int isInList( struct dllheader *L, int val) struct lnode findNode ( struct dllheader L, int val) void insertAfter( struct dllheader *L, int val, struct lnode p) void insertBefore( struct dllheader L, int val, struct lnode p void printerF struct dllheader alist) printf (" In") void printerR( struct dllheader alist ) printf("- Reverse printf ('" In") #include "dll.h" int main ) struct dllheader L; struct lnode *tmp; int i, x; L-makelist); - makelist insertBack( L, 789 printerFL for (i 0; i >>>alue to search: " scanf ("%d", &x); i= isinlist (L, x) ; printf ("I is %d ", i); tmpfindNode (L, x) if (tmp-NULL) printf ("NOPE ") else printf("Found node %d ", tmp->data); /fiqure out insertBefore and insertAfter return 0 #include #include struct lnode int data; struct lnode *prev: struct lnode *next; struct dllheader struct lnode *first; struct lnode last; int len; struct dllheader *makelist( struct Inode makenode ( int val ; void insertFront( struct dllheader L, int val void insertBack struct dllheader *L, int val): int isInList ( struct dllheader *L, int val struct lnode *findNode struct dl void insertAfter struct dllheader L, int val, struct lnode *p void insertBefore ( struct dllheader *L, int val, struct lnode *p void printerF struct dllheader alist void printerR struct dilheader *alist lheader *L, int val )