嵌套鏈表打印問題

Question

當我運行此代碼並調用「List（）」函數時，它僅打印用戶添加的最後一個。我希望從頭到尾打印。我希望你能幫助我瞭解我的清單功能。它只打印最後一個。

#include<stdio.h> 
#include <stdlib.h> 
#include <conio.h> 
#include <string.h> 

struct seat { 
    int k_no; 
    int k_name; 
    struct seat *next_k,*previous_k; 
} *first_k,*temp_k,*last_k; 


struct sefer { 
    char name[20]; 
    int no; 
    struct sefer *next,*previous; 
    struct seat *bus; 
} *first,*last,*temp; 

void list(); 
void seat_link(int val); 
void sefer_search(); 

int main() 
{ 
    int val; 
    printf ("how many names do you want to type ->"); 
    scanf ("%d",&val); 

    int i; 
    int j; 

    for(i=0;i<val;i++) {  
     if (first==NULL) { 
      first =(sefer *)malloc(sizeof(struct sefer)); 
      fflush(stdin); 
      printf (" %d. name->",i+1); 
      scanf ("%s",&first->name); 

      printf (" %d. capacity ->",i+1); 
      scanf ("%d",&first->no); 

      first->next=NULL; //2 inci düğüm daha oluşmadığı için null 
      first->previous=NULL; 
      last=first; //şimdilik sadece ilk düğüm olduğu için aynı zamanda son oluo 

      last->bus=NULL; 

      for(j=0;j<first->no;j++) { 

       //KOLTUKLAR OLUŞTURULCAK 

       if (last->bus==NULL){ 

        first_k =(seat *)malloc(sizeof(struct seat)); 
        fflush(stdin); 

        first_k->k_no=j; 
        first_k->k_name=1; 

        first_k->next_k=NULL; 
        first_k->previous_k=NULL; 
        last_k=first_k; 
        last->bus=first_k;     
       }  
       else { 

        temp_k =(seat *)malloc(sizeof(struct seat)); 
        fflush(stdin); 

        temp_k->k_no=j; 
        temp_k->k_name=0; 

        last_k->next_k=temp_k; 
        temp_k->previous_k=last_k; 
        last_k=temp_k; 
        last_k->last_k=NULL;    
       }  
      } 
     } 
     else if (last==first) { 
      printf ("\n"); 
      last = (sefer *)malloc(sizeof(struct sefer)); 
      fflush(stdin); 
      printf (" %d. name ->",i+1); 
      scanf ("%s",&last->name); 

      printf (" %d. capacitiy ->",i+1); 
      scanf ("%d",&last->no); 


      first->next=last; 
      last>next=NULL; 
      last->previous=first; 

      last->bus=NULL; 

      for(j=0;j<last->no;j++) { 

       //KOLTUKLAR OLUŞTURULCAK 

       if (last->bus==NULL) { 

        first_k =(seat *)malloc(sizeof(struct seat)); 
        fflush(stdin); 

        first_k->k_no=j; 
        first_k->k_name=2; 

        first_k->last_k=NULL; 
        first_k->previous_k=NULL; 
        last_k=first_k; 
        last->bus=first_k; 

       } 
       else {  
        temp_k =(seat *)malloc(sizeof(struct seat)); 
        fflush(stdin); 

        temp_k->k_no=j; 
        temp_k->k_name=0; 

        last_k->next_k=temp_k; 
        temp_k->previous_k=last_k; 
        last_k=temp_k; 
        last_k->last_k=NULL; 
       }  
      } 
     }   
     else { // kayıt eklenmişse diğer düğümler oluşturulcak  
      printf ("\n"); 
      temp=(sefer *) malloc(sizeof(struct sefer)); 
      fflush(stdin); 
      printf (" %d. name",i+1); 
      scanf ("%s",&temp->name); 

      printf (" %d. capacity->",i+1); 
      scanf ("%d",&temp->no); 

      last->next=temp; 
      temp->previous=last; 
      last=temp; 
      last->next=NULL; 

      last->bus=NULL; 

      for(j=0;j<temp->no;j++){ 

       //KOLTUKLAR OLUŞTURULCAK 

       if (last->bus==NULL){ 
        first_k =(seat*)malloc(sizeof(struct seat)); 
        fflush(stdin); 

        first_k->k_no=j; 
        first_k->k_name=3; 

        first_k->last_k=NULL; 
        first_k->previous_k=NULL; 
        last_k=first_k; 
        last->bus=first_k; 

       } 
       else{ 
        temp_k =(seat *)malloc(sizeof(struct seat)); 
        fflush(stdin); 

        temp_k->k_no=j; 
        temp_k->k_name=0; 

        last_k->next_k=temp_k; 
        temp_k->previous_k=last_k; 
        last_k=temp_k; 
        last_k->next_k=NULL; 
       }  
      } 
     } 
    } 

    list(); 
    system("PAUSE"); 
    return 0;   
} 


void sefer_search(){ //bağda arama yapar 

    int searching; 

    printf ("\n\t\t Aranacak Sefer Numarasını Giriniz:"); 
    scanf ("%d",&searching); 

    temp=first; 

    while (1) { 
     if (temp->no==searching) { 
      break; 
     } 
     temp=temp->next; 
    } 
} 


void seat_link(int val) { 
    int j;    
} 

我的問題是在這裏實際上是：

void list(){ 
    temp=first; 
    while (temp !=NULL) { 
     printf("\t%s --%d \n", temp->name,temp->no); 
     temp=temp->next; 
    }   

    printf ("\n"); 

    last->bus=first_k; 
    while (last->bus !=NULL) {    
     printf("\t%d --%d \n",last->bus->k_name,last->otobus->k_no); 
     last->bus=last->bus->next_k;  
    } 
} 

請幫我

Answer 1

你的代碼有一堆問題。首先，它不會因各種原因而編譯。例如，你有時使用struct koltuk而沒有定義它。 「koltuk」意思是土耳其語中的「座位」，所以我將假設在所有這些情況下你的意思是struct seat。其次，deg未定義;我假定你的意思是val。

還有其他一些問題，如我能夠通過做出合理的猜測來解決的問題。但還有以下基本問題：

1. 您使用全局變量作爲局部變量，例如temp_k和temp。這使得人們幾乎不可能分析你的代碼並理解控制流程。

2. 你已經複製代碼到處都是。您有三個獨立的代碼塊來分配和初始化sefer，具體取決於它是全局鏈表中的第一個，第二個還是更高。使用子程序！

3. 您的數據模型似乎很混亂。你有全局變量struct *first_k,*temp_k,*last_k;，這使得它看起來像你有一個全局鏈接的所有sefer結構的鏈接列表，但是struct seat沒有以明顯的方式返回到擁有它的sefer，這意味着每個sefer都有一個單獨的，私人名單seat s。

把所有這三個問題放在一起，我不能真正看到哪裏，特別是你會出錯。爲了消除這些問題，我重新編寫了代碼。試試吧，看它是否解決你的問題：

#include <stdio.h> 
#include <stdlib.h> 
#include <conio.h> 
#include <string.h> 

typedef struct seat{ 
    int k_no; 
    int k_name; 
    struct seat *next_k, *previous_k; 

} seat; 

typedef struct sefer { 
    char name[20]; 
    int no; 
    struct sefer *next,*previous; 
    struct seat *bus; 

} sefer; 

void list(); 

sefer *sefer_search(); 

void link_sefer(sefer **pp_first, sefer **pp_last, sefer *p_added) 
{ 
    p_added->next = p_added->previous = NULL; 
    if (*pp_first == NULL) 
    { 
     *pp_first = *pp_last = p_added; 
    } 
    else 
    { 
     (*pp_last)->next = p_added; 
     p_added->previous = *pp_last; 
     *pp_last = p_added; 
    } 
} 

void link_seat(seat **pp_first, seat **pp_last, seat *p_added) 
{ 
    p_added->next_k = p_added->previous_k = NULL; 
    if (*pp_first == NULL) 
    { 
     *pp_first = *pp_last = p_added; 
    } 
    else 
    { 
     (*pp_last)->next_k = p_added; 
     p_added->previous_k = *pp_last; 
     *pp_last = p_added; 
    } 
} 

sefer *create_and_link_sefer(sefer **pp_first_sefer, sefer **pp_last_sefer, int i) 
{ 
    sefer *new_sefer; 
    seat *p_first_seat = NULL; 
    seat *p_last_seat = NULL; 
    int j; 


    // Allocate and initialize sefer 

    printf ("\n"); 
    new_sefer = calloc(1, sizeof(struct sefer)); 
    fflush(stdin); 
    printf (" %d. name->",i+1); 
    scanf ("%s",&new_sefer->name); 

    printf (" %d. capacity->",i+1); 
    scanf ("%d",&new_sefer->no); 
    new_sefer->bus = NULL; 

    // Link sefer 

    link_sefer(pp_first_sefer, pp_last_sefer, new_sefer); 

    // Allocate seats 
    for(j=0;j<new_sefer->no;j++){ 

     //KOLTUKLAR OLUŞTURULCAK 
     seat *p_seat = calloc(1, sizeof(struct seat)); 
     fflush(stdin); 
     p_seat->k_no=j; 
     p_seat->k_name = (j != 0 ? 0 : (i+1 > 3 ? 3 : i+1)); // I CAN'T FIGURE OUT WHAT THIS IS SUPPOSED TO BE 

     link_seat(&p_first_seat, &p_last_seat, p_seat); 
    } 

    new_sefer->bus = p_first_seat; 

    return new_sefer; 
} 

void sefer_list(sefer *first, sefer *last){ 

    sefer *temp=first; 
    while (temp !=NULL) 
    { 
     seat *seat; 

     printf("\t%s --%d \n", temp->name,temp->no); 

     for (seat = temp->bus; seat != NULL; seat = seat->next_k) 
     { 
      printf("\t\t%d --%d \n",seat->k_name, seat->k_no); 
     } 

     printf ("\n"); 
     temp=temp->next; 
    } 
} 

sefer *sefer_search(sefer *first, sefer *last){ //bağda arama yapar 

    int arama; 
    sefer *temp; 

    printf ("\n\t\t Aranacak Sefer Numarasını Giriniz:"); 
    scanf ("%d",&arama); 

    temp=first; 

    while (temp != NULL){ 

     if (temp->no==arama){ 
      break; 
     } 

     temp=temp->next; 
    } 

    return temp; 
} 

sefer *first = NULL; 
sefer *last = NULL; 

int main() 
{ 
    int val; 
    int i; 

    printf ("how many names do you want to type ->"); 
    scanf ("%d",&val); 

    for(i=0;i<val;i++){ 
     create_and_link_sefer(&first, &last, i); 
    } 

    sefer_list(first, last); 

    system("PAUSE"); 
    return 0; 
} 

看來工作，但因爲我不知道你正在嘗試做的做，它可能無法正常工作，只要你想。

Answer 2

由邏輯，這意味着temp還真是不會去任何地方看。我的猜測是，當您在main的前幾行中設置指針*first, *last, *temp;時，您確實沒有指向first到NULL，導致它跳過第一個if語句。指針默認不指向NULL，它們指向事先在該內存位置的任何內容。在這種情況下，垃圾。嘗試在第一個if語句之前添加first=NULL;。