链接列表程序显示学生标记

时间:2014-11-22 21:48:28

标签: c linked-list malloc displaylist httpunhandledexception

 #include<stdio.h>

 #include<conio.h>

 #include<stdlib.h>

 void Insert();
 void DisplayList();
 struct Student
 {
 char Name[10];
 int Marks;
 struct Student *Next;
 } *Start;
 int main()
 {
 Start = NULL;
 int Choise;
 while (1)
 {
 printf("enter number to choose ");
 scanf_s("%d", &Choise);
 switch (Choise)
 {
 case 1:
    Insert();
    break;
    case 3:
        DisplayList();
        break;
    default:
    printf("Incorrect assignment Press relevant key :");
    }
    }
    }
    void Insert()
    {
    struct Student *Temp, *current=NULL;
    Temp = (struct Student *) malloc(sizeof(struct Student));
    printf("Enter Name Of Student");
    scanf_s("%s",&Temp->Name);
    printf("Enter Marks Of Student");
    scanf_s("%d", &Temp->Marks);
    Temp->Next = NULL;
    if (Start == NULL)
    {
        Start = Temp;
        Temp->Next = NULL;
    }
     else
        current = Start;
        while (current->Next != NULL)
        {
        current = current->Next;
        current->Next = Temp;
        }
    }
  void DisplayList()
   {
    struct Student *current, *Temp;
    current = Start->Next;
    if (Start == NULL)
    {
        printf("No Element in the list");
    }
    else
    {
        for (current = Start; current != NULL; current = current->Next)
        {
            printf("The List are\n");
            printf_s("%d",current->Marks);
        }

    }

这是为单个链表编写的程序。当我显示列表时,它只给出列表中的一个元素。每当我尝试打印链表的元素时,它只给输出一个元素 我做了什么错误请帮忙?

3 个答案:

答案 0 :(得分:1)

变化

else
    current = Start;
    while (current->Next != NULL)
    {
    current = current->Next;
    current->Next = Temp;
    }

else {
    current = Start;
    while (current->Next != NULL)
    {
        current = current->Next;
    }
    current->Next = Temp;
}

scanf_s("%s", Temp->Name, sizeof(Temp->Name)); //remove & and add size(see Amnon's answer)

答案 1 :(得分:1)

当使用scanf_s这是scanf的安全版本时,您不仅要传递缓冲区的地址,还要传递它的大小作为下一个参数,即:

scanf_s("%s", Temp->Name, _countof(Temp->Name));

您可以在http://msdn.microsoft.com/en-us/library/w40768et.aspx

中详细了解相关信息

代码的另一个问题是,您使用current初始化NULL,然后尝试访问其Next字段。

答案 2 :(得分:0)

在此更改代码:

  else
     current = Start;
     while (current->Next != NULL)
    {
     current = current->Next;
     current->Next = Temp;
     }

到此:

else {
     current = Start;
      while (current->Next != NULL)
      {
      current = current->Next;
       }
      current->Next = Temp;
      temp->next=NULL;
    }

你忘记在下一个指针处添加NULL,因此你只得到单个输出。