Double-linked list insertion

Pre-compilation

#include <stdlib.h><stdio.h>#define status int#define TRUE 1#define FALSE 0

struct node{    int value;            /*  */    struct NODE *prev;  /*  */    struct NODE *next;  /*  */}node;

Data Structure

1 /*2 function Description:3 inserting new nodes (from small to large)4 5 Parameters:6 ROOTP--a double pointer to the root node7 New_value--To insert a new value for the linked list8 9 return Value:Ten returns True if the insert succeeds; One Otherwise, returns false A */ - Status -Insert (Node **ROOTP,intnew_value) the { -Node *current = *ROOTP;  -Node *_new =NULL; -  +     /*Find insertion Position*/ -      while(Current! =NULL) { +         if(Current->value >new_value) A              Break; at  -         if(Current->value = =new_value) { -printf"value%d already exists \ n", new_value); -             returnFALSE; -         } -Current = Current->Next; in     } -  to     /*Create a new node*/ +_new = (Node *)malloc(sizeof(Node)); -     if(_new = =NULL) { theprintf"not enough memory \ n" ); *         returnFALSE; $     }Panax Notoginseng_new->value =New_value; -  the     /*Insert new node*/ +     if(Current = =NULL) { A         if(current = = *ROOTP) {/*insert to empty list*/ the*ROOTP =_new; +_new->prev =_new; -_new->next =NULL; $          $}Else{/*Insert to Trailer*/ -_new->next =NULL; -_new->prev = (*ROOTP)prev; the(*ROOTP)->prev->next =_new; -(*ROOTP)->prev =_new;Wuyi         } the}Else{ -         if(current = = *ROOTP) {/*before inserting to the root node*/ Wu_new->prev = (*ROOTP)prev; -_new->next =Current ; AboutCurrent->prev =_new; $*ROOTP =_new; -  -}Else{/*before inserting a node in the middle.*/ -_new->prev = current->prev; ACurrent->prev->next =_new; +_new->next =Current ; theCurrent->prev =_new; -         } $     } the  the     returnTRUE; the}

inserting code

1 /*2 function Description:3 inserting new nodes (from small to large)4 5 Parameters:6 ROOTP--a double pointer to the root node7 New_value--To insert a new value for the linked list8 9 return Value:Ten returns True if the insert succeeds; One Otherwise, returns false A */ - Status -Insert (Node **ROOTP,intnew_value) the { -Node *current = *ROOTP;  -Node *_new =NULL; -  +     /*Find insertion Position*/ -      while(Current! =NULL) { +         if(Current->value >new_value) A              Break; at  -         if(Current->value = =new_value) { -printf"value%d already exists \ n", new_value); -             returnFALSE; -         } -Current = Current->Next; in     } -  to     /*Create a new node*/ +_new = (Node *)malloc(sizeof(Node)); -     if(_new = =NULL) { theprintf"not enough memory \ n" ); *         returnFALSE; $     }Panax Notoginseng_new->value =New_value; -  the     /*Insert new node*/ +     if(current = = NULL) {/*To insert a root or tail node.*/ A         if(Current! = *ROOTP) { the(*ROOTP)->prev->next =_new;  +         } -_new->prev = (current = = *ROOTP)? _new: (*ROOTP)prev; $_new->next =NULL; $(current = = *ROOTP)? *ROOTP: (*ROOTP)->prev) =_new; -          -}Else{/*before inserting to the root node or the middle node.*/ the_new->prev = current->prev; -(current = = *ROOTP)? current->prev:current->prev->next) =_new;Wuyi_new->next =Current ; the(current = = *ROOTP)? *rootp:current->prev) =_new; -     } Wu  -     returnTRUE; About}

Optimized Insert Code

Double-linked list insertion