Question

我正在编写一个程序查询该用户的员工信息，例如名字，姓氏和三位数的员工ID号。结构和链表用于存储数据。遍历链表发生，并显示具有最高ID号的员工的信息。我试图定义到目前为止具有最大ID的员工的指针，然后在循环中遍历列表，如果当前ID大于前一个，则替换指针。我脑子里有这个想法和纸上的逻辑，但我很不确定如何将这个过程形成代码。

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

typedef struct employee
{  char fname [21];
   char lname [21];
   int id;
   struct employee *next;
}DATA;

DATA* insertit (DATA *first, char firstn[], char lastn[], int idnum);

int main (void)
{
  DATA *head,
           *p;
  char firstname[21];
  char lastname[21];
  int idnumber,
             j,
             k,
             n;
  char ch,
       nl;

  head=NULL;
  for (j=0; j<21; j++)
    firstname[j]=' ';
  printf("Please enter the number of employees to enter information about:   ");
  scanf("%d", &n);

  for(k=0; k<n; k++)
    { printf("Please enter the employee's first name: \n");
      scanf("%s", firstname);
      printf("Please enter the employee's last name: \n");
      scanf("%s", lastname);
      printf("Please enter the employee's three digit id number: \n");
      scanf("%d", &idnumber);
      scanf("%c", &nl);
      head=insertit(head, firstname, lastname, idnumber);
      for (j=0; j<21; j++)
        firstname[j]= ' ';
   }
  p=head;
  while (p!=NULL)
  { printf("\n");
    printf("The employee's first name is: %s \n", p->fname);
    printf("The employee's last name is: %s \n", p->lname);
    printf("The employee's id number is: %d\n", p->id);
    p=p->next;
  }
printf("Hit any character to continue.");
scanf("%c", &ch);
}

DATA* insertit(DATA *first, char firstn[], char lastn[], int idnum)
/*Function to insert data into a linked list.*/

{
  DATA *p,
       *q,
    *newp;
  int found,
        len,
          i;
  found=0;
  q=first;
  p=first;

  while ((p!=NULL) && (!found))
  { if ((p->id < idnum) || (p-> id == idnum))
    { q=p;
      p=p->next;
    }
   else
     found=1;
  }
newp=(DATA *)malloc(sizeof(DATA));
newp->id=idnum;
strncpy(newp-> fname, firstn, 21);
strncpy(newp-> lname, lastn, 21);
newp->next=p;
if (q!=p)
  q->next=newp;
else
  first=newp;
return (first);
}

所以，通过我的逻辑，我在想以下几点：

while（z = 0; zsmall） { printf（＆＃34;身份证号码最高的员工具有以下名字：％s \ n＆＃34;，p-＆gt; fname）; printf（＆＃34;身份证号码最高的员工姓氏如下：％s \ n＆＃34;，p-＆gt; lname）; printf（＆＃34;身份证号码最高的员工具有以下身份证号码：％d \ n＆＃34;，p-＆gt; id）; } }

所以，感谢一位用户，我现在有以下代码：

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

typedef struct employee
{  char fname [21];
   char lname [21];
   int id;
   struct employee *next;
}DATA;

DATA* insertit (DATA *first, char firstn[], char lastn[], int idnum);
void printmax(DATA *head);

int main (void)
{
  DATA *head,
           *q,
           *p;
  char firstname[21];
  char lastname[21];
  int idnumber,
             j,
             k,
             n;
  char ch,
       nl;

  head=NULL;
  for (j=0; j<21; j++)
    firstname[j]=' ';
  printf("Please enter the number of employees that you would like to enter information about: ");
  scanf("%d", &n);

  for(k=0; k<n; k++)
    { printf("Please enter the employee's first name: \n");
      scanf("%s", firstname);
      printf("Please enter the employee's last name: \n");
      scanf("%s", lastname);
      printf("Please enter the employee's three digit id number: \n");
      scanf("%d", &idnumber);
      scanf("%c", &nl);
      head=insertit(head, firstname, lastname, idnumber);
      for (j=0; j<21; j++)
        firstname[j]= ' ';
   }
  p=head;
  while (p!=NULL)
  { printf("\n");
    printf("The employee's first name is: %s \n", p->fname);
    printf("The employee's last name is: %s \n", p->lname);
    printf("The employee's id number is: %d\n", p->id);
    p=p->next;
  }
  printf("Hit any character to continue."); scanf("%c", &ch);
}

DATA* insertit(DATA *first, char firstn[], char lastn[], int idnum)
/*Function to insert data into a linked list.*/
{
  DATA *p,
       *q,
    *newp;
  int found,
        len,
          i;
  found=0;
  q=first;
  p=first;

  while ((p!=NULL) && (!found))
  { if ((p->id < idnum) || (p-> id == idnum))
    { q=p;
      p=p->next;
    }
   else
 found=1;
  }
newp=(DATA *)malloc(sizeof(DATA));
newp->id=idnum;
strncpy(newp-> fname, firstn, 21);
strncpy(newp-> lname, lastn, 21);
newp->next=p;
if (q!=p)
  q->next=newp;
else
  first=newp;
return (first);
}

void printmax (DATA *head)
{
  DATA *highest = head;
  DATA *next = head.next;
  while (next != NULL) 
     {
      if (next->highid > highest->highid) {
      highest = next;
      }
    next = next->next;
  }
  printf("The employee with the highest id number has the first name: %s\n",highest->fname);
  printf("The employee with the highest id number has the last name: %s\n",highest->lname);
  printf("The employee with the highest id number has the id number: %d\n", highest->id);
 }
}

我已经手动跟踪程序，它似乎工作正常，但是当我编译它时，会发生以下错误：

错误：请求成员'next'不是结构或联合 DATA * next = head.next;
错误：'DATA'没有名为'highid'的成员 if（next-＆gt; highid＆gt; highest-＆gt; highid）{
错误：'DATA'没有名为'highid'的成员 if（next-＆gt; highid＆gt; highest-＆gt; highid）{

我不熟悉这些错误消息，所以我研究了它们以确定它们的原因，但是，我仍然不确定。因此，如果有人能解释原因并可能解决问题，我将不胜感激。到目前为止，我非常感谢你们的帮助。

Answer 1

找到最高的员工并打印出来。

void PritMax(const DATA *head) {
  const DATA *highest = head;
  const DATA *next = head->next;
  while (next != NULL) {
    if (next->id > highest->id) {
      highest = next;
    }
    next = next->next;
  }
  printf("The employee with the highest id number has the first name: %s\n",
      highest->fname);
  printf("The employee with the highest id number has the last name: %s\n",
      highest->lname);
  printf("The employee with the highest id number has the id number: %d\n",
      highest->id);
}

排序链表中的最高编号

1 个答案: