移動指針以便以不同的順序打印

Question

我必須完成此程序。

我有這樣的

Name iD Num_of_elements elem(1) elem(2), ... , elem(n) 
james 1 3 AAA BBB CCC 
arthur 2 2 EEE FFF 
james 1 1 KKK 
irine 3 4 EEE FFF DDD AAA 
james 1 1 XXX 

我需要創建一個列表，將文件加載到列表中，並打印責令如下文件：

james 1 3 AAA BBB CCC 
james 1 1 XXX 
james 1 1 KKK 
arthur 2 2 EEE FFF 
irine 3 4 EEE FFF DDD AAA 

（這是必要的打印之前具有相同iD的人員，然後打印其他人員）。

我已經在ANSI C中創建了程序的一部分，但是我無法按請求完成「最終功能」。

無效printListOrderedByiD（結構清單*頂部） {}

這是我的代碼

#include <stdio.h> 
#include <stdlib.h> 
#include <string.h> 
#define len 35 

struct elements 
{ 
    char name[len]; 
}; 

struct list 
{ 
    char name[len]; 
    int id; 
    int numOfElements; 
    struct elements *pElements; /* pointer to the struct elements */ 
    struct list *next; 
}; 


FILE *openFile(FILE *fp) 
{ 
    fp=fopen("file.txt", "r"); 
     if (fp==NULL) 
      { 
       perror(""); 
       exit(1); 
      } 
    return (fp); 
} 


struct list *newNode(FILE *fp) 
{ 
    int i=0; 
    struct list *temp=(struct list *)malloc(sizeof(struct list)); 

    fscanf(fp, "%s\t%d\t%d\t", temp->name, &temp->id, &temp->numOfElements); 

    temp->pElements=(struct elements *)malloc(temp->numOfElements*sizeof(struct elements)); 

     for (i=0; i<temp->numOfElements; i++) 
     { 
      fscanf(fp, "%s\t", temp->pElements[i].name); 
     } 

     temp->next=NULL; 

    return temp; 
} 

struct list *insertAsLast(struct list *top, FILE *fp) /* this function will insert every node at the end of the list */ 
{ 
    if (top==NULL) 
    { 
     top=newNode(fp); 
    } 
    else 
    { 
     top->next=insertAsLast(top->next, fp); 
    } 

return top; 
} 

void printList(struct list *top) /* this procedure will stamp the list as loades from the file */ 
{ 
    int i=0; 

    if (top==NULL) 
    { 
     printf("//\n"); 
    } 
    else 
    { 
     printf("%s %d %d ", top->name, top->id, top->numOfElements); 

      for (i=0; i<top->numOfElements; i++) 
      { 
       printf("%s ", top->pElements[i].name); 
      } 
      printf("\n"); 

     printList(top->next); 
    } 
} 


int main() 
{ 
    struct list *top=NULL; 
    char firstLine[200]; 
    FILE *fp=NULL; 
    fp=openFile(fp); 

     fgets(firstLine, 200, fp); /* in order to jump the 1st line */ 

      while (!feof(fp)) 
      { 
       top=insertAsLast(top, fp); 
      } 
    fclose (fp); 

    printList(top); 

    return 0; 
} 

任何人能幫助我嗎？

Answer 1

按臨時存儲在陣列中的ID進行排序。

static int cmp(const void *a, const void *b){ 
    int x = (*(struct list**)a)->id; 
    int y = (*(struct list**)b)->id; 
    return x < y ? -1 : x > y; 
} 
void printListOrderdByID(struct list *top){ 
    struct list **table, *p; 
    size_t size=16, n=0, i; 
    table = malloc(size*sizeof(struct list*)); 
    //Can be secured in the malloc simply if you use it the number of elements already known from a reading from a file. 
    for(p=top; p ; p=p->next){ 
     table[n++] = p; 
     if(n == size) 
      table = realloc(table, (size+=16)*sizeof(struct list*)); 
    } 
    qsort(table, n, sizeof *table, cmp); 
    for(i = 0; i < n; ++i){ 
     int j; 
     p = table[i]; 
     printf("%s %d %d ", p->name, p->id, p->numOfElements); 
     for (j=0; j<p->numOfElements; j++){ 
      printf("%s ", p->pElements[j].name); 
     } 
     printf("\n"); 
    } 
    free(table); 
}