链表的学习--创建、添加和删除元素

//list.cpp
#include "list.h"
#include <stdlib.h>
#include <stdio.h>

void initList(List *list) {
    list->first = NULL;
}

void destroyList(List *list) {
    Element *e = list->first;
    Element *next = list->first;
    list->first = NULL;
    while (e) {
        next = e->next;     // e->next wird zwischengespeichert
        e->next = NULL;     // und bleibt erreichbar, nachdem e
        free(e);            // freigegeben wurde.
        e = next;
    }
}

void prependToList(List *list, int i) {
   Element *e = malloc(sizeof(Element)); 
   e->value = i;

   e->next = list->first;
   list->first = e;
}

void printList(List *list) {
    Element *e;
    for (e = list->first; e != NULL; e = e->next) {
        printf("%i ", e->value);
    }
    printf("
");
}

size_t sizeOfList(List *list) {
    Element *e;
    size_t count = 0;
    // Iterationsbedingung ist wahr, wenn e != NULL
    for (e = list->first; e; e = e->next) {
        count++;
    }

    return count;
}

void appendToList(List  *list,int i) {
    Element *e;
    e = list->first;
    if(e==NULL){
      e=malloc(sizeof(Element));
      e->value=i;
      e->next = NULL;
      list->first=e;
      return;
    }
    while(e->next != NULL)
    {
    e = e->next;
    }
    
    e->next=malloc(sizeof(Element));
    e->next->value = i;
    e->next->next=NULL;
}

int removeFirst(List  *list) {
    Element *e;
    int temp;
    e = list->first;
    if(e == NULL){
      printf("List is NULL!
");
      return 0;
    }
    temp=e->value;
    list->first = list->first->next;
    free(e);
    return temp;
}

int removeLast(List  *list) {
    Element *e;
    int temp;
    e = list->first;
    if(e == NULL){
      printf("List is NULL!
");
      return 0;
    }
    if(e->next== NULL)
    {
      return removeFirst(list);
    }
    while(e->next->next != NULL)
    {
    e = e->next;
    }
    temp=e->next->value;
    free(e->next);
    e->next = NULL;
    return temp;
}

void insertAfterPosition(List  *list, size_t  pos, int i) {
    Element *e,*g;
    e = list->first;
    if(e == NULL){
      printf("List is NULL!
");
      return;
    }
    if(pos>sizeOfList(list))//new add
    {
      printf("pos is larger than size of list!
");
      return;
    }
    size_t j;
    for (j=0; j<pos-1; j++)
    {
       e = e->next;
    }

    g=malloc(sizeof(Element));
    g->value=i;
    g->next=e->next;
    e->next=g;

}

int removeAfterPosition(List *list,size_t  pos){
    Element *e,*g;
    int temp;
    e = list->first;
    if(e == NULL){
      printf("List is NULL!
");
      return 0;
    }
    if(pos>sizeOfList(list))//new add
    {
      printf("pos is larger than size of list!
");
      return 0;
    }
    size_t j;
    for (j=0; j<pos-1; j++)
    {
       e = e->next;
    }

    g=e->next;
    temp=g->value;
    e->next=e->next->next;
    free(g);
    return temp;
}

void insertSorted(List  *list, int i) {
    Element *e,*g;
    e = list->first;
    if(e == NULL){
      printf("List is NULL!
");
      return;
    }
    
    if(list->first->next== NULL)
    {
        prependToList(list, i);
        sortList(list);
        return;
    }
        
    for(e = list->first; e->next != NULL; e = e->next){
    if((e->value)>(e->next->value)){
       sortList(list);
       break;
     }
    }

    g=malloc(sizeof(Element));
    g->value=i;

    if(i<=list->first->value)//new add
    {
    prependToList(list, i);
        return;
    }

    for(e = list->first; e->next != NULL; e = e->next){
      if((e->value<=i)&&(e->next->value>=i)){
          g->next=e->next;
          e->next=g;
          break;
       }
    }
    if(e->next == NULL)//new add
    {
    e->next=g;
        g->next=NULL;
    }
}

void sortList( List *list) {
    Element *e;
    int temp;
    size_t j;
    size_t size=sizeOfList(list);
    for (j = size - 1; j > 0; j--)
    {
      size_t p = 0;
      for(e = list->first; e->next != NULL; e = e->next){
          p++;
          if (p > j) break;
         if((e->value)>(e->next->value)){
            temp=e->value;
            (e->value)=(e->next->value);
            (e->next->value)=temp;
           }
       }
    }

}

//list.h
#include <stddef.h> // enthält Definition von size_t

struct Element {
    int value;
    struct Element *next;
};

struct List {
    struct Element *first;
};

typedef struct List List;
typedef struct Element Element;

void initList(List* list);
void destroyList(List *list);
int removeFirst(List  *list);
void appendToList(List  *list,int i);
void printList(List *list);
int removeLast(List  *list);
size_t sizeOfList(List *list);
void insertAfterPosition(List  *list, size_t  pos, int i);
void prependToList(List *list, int value);
void insertSorted(List  *list, int i);
void sortList( List *list);
int removeAfterPosition(List *list,size_t  pos);

//prog.cpp
#include "list.h"
#include <stdio.h>

int main() {
    struct List list;
    int appnum,insertpos,removepos,insertnum,insertsortnum;
    initList(&list);

    int i = 0;
    for (i=5; i < 15; ++i) {
        prependToList(&list, i);
    }
    printList(&list);
    printf("Please input append number:");
    scanf("%d",&appnum);
    printf("Size of list: %zu
", sizeOfList(&list));
    appendToList(&list, appnum);
    printf("appendToList:
");
    printList(&list);
    printf("Size of list: %zu
", sizeOfList(&list));
    removeFirst(&list);
    printf("removeFirst:
");
    printList(&list);
    printf("Size of list: %zu
", sizeOfList(&list));
    removeLast(&list);
    printf("removeLast:
");
    printList(&list);
    printf("Size of list: %zu
", sizeOfList(&list));
    printf("Please input insert position and number:");
    scanf("%d %d",&insertpos,&insertnum);
    insertAfterPosition(&list,insertpos,insertnum);
    printf("insertAfterPosition %d:
",insertpos);
    printList(&list);
    printf("Please input remove position:");
    scanf("%d",&removepos);
    removeAfterPosition(&list,removepos);
    printf("removeAfterPosition %d:
",removepos);
    printList(&list);
    printf("Please input insertsorted number:");
    scanf("%d",&insertsortnum);
    printf("Size of list: %zu
", sizeOfList(&list));
    insertSorted(&list,insertsortnum);
    printf("insertSorted:
");
    printList(&list);
    printf("Size of list: %zu
", sizeOfList(&list));
    destroyList(&list);
    printf("Size of list: %zu
", sizeOfList(&list));
}