Listen Cheat Sheet by TimSch

extern TData *First = NULL; 
 extern TData *Last = NULL;

int append­InL­ist­(TData *Neu) 
 { 
   //prüfen, ob neues Element existiert 
   if (Neu == NULL) 
     return 0; 
 
   //Neues Element ist neues Listenende 
   Neu->Next = NULL; 
 
   if (First == NULL) 
     //Fall 1: Liste ist leer 
     First = Last = Neu; 
   else 
     //Fall 2: Liste ist nicht leer 
     Last = Last->Next = Neu; 
   return 1; 
 }

TData *remov­eFr­omL­ist(int delIndex) 
 { 
    TData tmp = NULL, prev = NULL;  
    // Fall 1: Liste leer? 
    if (First == NULL) 
       return NULL; 
   
    // Fall 2: Listen­anfang entfernen? 
    if (First­->Index == delIndex) 
    { 
       tmp = First; 
       // nur ein Element in Liste? 
       if (Last == First) 
          Last = NULL; 
       First = First-­>Next; 
       return tmp; 
    } 
   
    // Fall 3: zu entfer­nendes Element suchen 
    prev = First; 
    tmp = prev->­Next; 
    while (tmp != NULL) 
    { 
       if (tmp->­Index == delIndex) 
       { 
          prev->Next = tmp->Next; 
          if (tmp == Last) // letztes Element entfernt? 
             Last = prev; 
          return tmp; 
       } 
       prev = tmp; 
       tmp = tmp->Next; 
    } 
    return NULL; 
  }

int insert­InL­ist­(TData *Neu) 
 { 
   ­TData *tmp = First; 
    
   ­//p­rüfen, ob neues Element existiert 
   ­if(Neu == NULL) 
     ­return 0; 
      
   ­if(­First == NULL) 
   { //Fall 1: Liste ist leer 
     ­Neu­->Next = Neu->Prev = NULL; 
     ­First = Last = Neu; 
     ­return 1; 
   } 
    
   if (First­->Value >= Neu->V­alue( 
   { //Fall 2: am Listen­anfang einfügen 
     ­Neu­->Next = First; 
     ­Neu­->Prev = NULL; 
     ­First = First-­>Prev = Neu; 
     ­return 1; 
   } 
    
   if (Last-­>Value <= Neu->V­alue) 
   { //Fall 3: am Listenende anhängen 
     ­Neu­->Prev = Last; 
     ­Neu­->Next = NULL; 
     Last = Last->Next = Neu; 
     ­return 1; 
   } 
    
   ­//Fall 4: zwischen zwei Elemente einfügen 
   ­while (tmp->Next != NULL) 
   { //prüfen, ob neues Listen­element vor dem nächsten Listen­element eingefügt werden muss 
     if (tmp->­Nex­t->­Value >= Neu->V­alue) 
     { 
       ­Neu­->Next = tmp->Next; 
       ­Neu­->Prev = temp; 
       ­tmp­->Next = temp->­Nex­t->Prev = Neu; 
       ­return 1; 
     } 
     tmp = temp->­Next; 
   } 
   ­return 0; 
 } 

 typedef enum {forward, backward} TDirec­tion; 
   
 void printL­ist­(TD­ire­ction Direction) 
  { 
    TData *tmp = (Direction == forward) ? First : Last; 
    int Anzahl­Ele­mente = 0; 
   
    printf­("\n­Index "); 
    while (tmp) 
    { 
       printf­("| %3i ", tmp->I­ndex); 
       tmp = (Direction == forward) ? tmp->Next : tmp->Prev; 
       Anzahl­Ele­men­te++; 
    } 
   
    printf­("\n­---­---­"); 
    while (Anzah­lEl­eme­nte--) 
       printf­("--­---­-"); 
   
    printf­("\nWert "); 
    tmp = (Direction == forward) ? First : Last; 
    while (tmp != NULL) 
    { 
       printf­("| %3.0f ", tmp->V­alue); 
       tmp = (Direction == forward) ? tmp->Next : tmp->Prev; 
    } 
    printf­("\n­"); 
 }