函数检查C链表中是否存在字符串

我正在为课堂编写一个程序，我的老师让我们在添加之前检查一下列表中是否已经有名字。我为此编写的代码似乎工作不正常

    void doAdd (waitListPtr hd)
{
 /* get group size from input */
int size = getPosInt();
if (size < 1)
{
printf ("Error: Add command requires an integer value of at least 1\n");
printf ("Add command is of form: a <size> <name>\n");
printf ("  where: <size> is the size of the group making the reservation\n");
printf ("         <name> is the name of the group making the reservation\n");
return;
}

/* get group name from input */
char *name = getName();
 if (NULL == name)
{
printf ("Error: Add command requires a name to be given\n");
printf ("Add command is of form: a <size> <name>\n");
printf ("  where: <size> is the size of the group making the reservation\n");
printf ("         <name> is the name of the group making the reservation\n");
return;
}
    if(doesNameExist(hd, name) == TRUE){
        printf("\nERROR: Name already on list");
    }else{
    printf ("Adding group \"%s\" of size %d\n", name, size);
    addToList(&hd, size, name);
    hd->groupStatus = PRESENT;
    }
}

}

下面是我的链表结构的声明

typedef struct waitListStruct
{
char      groupName[30];
int       groupSize;
int       groupStatus;
struct    waitListStruct*  next;
} waitList;

typedef waitList* waitListPtr;

下面是向列表中添加新节点的函数

void addToList(waitListPtr* hd, int size, char* name){

waitListPtr ptr = (waitListPtr) malloc (sizeof(waitList));

strcpy(ptr->groupName, name);

ptr->groupSize = size;

ptr->next = *hd;

*hd = ptr;

}

这是main中调用函数的部分

int main (int argc, char **argv)
{

 waitListPtr head = NULL;


 while ((ch = getNextNWSChar ()) != EOF)
 {
if('a' == ch)
  {
   doAdd(head);
 }
 }
 }

谁能告诉我我做错了什么

if(strcmp(ptr->groupName, &name)== 0){

这是不对的。我很惊讶你的编译器没有将其标记为错误

它需要：

if(strcmp(ptr->groupName, name)== 0){
                    //   ^^ Drop the &

改进建议

该函数中的

while

循环可以简化为：

while(ptr != NULL)
{
   if (strcmp(ptr->groupName, name) == 0)
      return TRUE;

   ptr=ptr->next;
}

改变加法的逻辑

void addToList(waitListPtr* hd, int size, char* name){

waitListPtr ptr = (waitListPtr) malloc (sizeof(waitList));

strcpy(ptr->groupName, name);

ptr->groupSize = size;

if (*hd == NULL)
{
   ptr->next = NULL;
} else {
    ptr->next = *hd;
}
    *hd = ptr;
}

---

希望解决问题#和平

谢谢。刚试着去掉&，但我得到了同样的结果。知道还有什么问题吗？@wuddupjoe，这表示代码中的其他地方有问题。@wuddupjoe可能与您的

addToList

函数有关。问题是否可能是因为我如何将名称存储到链接列表中？这是我添加新节点的代码。void addToList（waitlistpr*hd，int size，char*name）{waitlistpr=（waitlistpr）malloc（sizeof（waitList））；strcpy（ptr->groupName，name）；ptr->groupSize=size；ptr->next=*hd；*hd=ptr；}@wuddupjoe，我的建议是在调用

strcmp

时应用我建议的修复程序来开始一篇新文章。如果我尝试用ptr.groupName替换ptr->groupName，我会收到一个错误，声明“在非结构或联合的内容中请求成员'groupName'”。我建议在这里发布完整的源代码，我可以帮助您。奇怪的是，hd不是ptr，你也不会出错。我目前无法发表新的帖子，因为它说我只能每90分钟发布一次问题。我有没有办法把代码传给你？@Sohil-Omer-typedef-waitList*waitListPtr；现在的问题是将名称添加到链接列表中

while(ptr != NULL){
    // Remove & from the name , Check man page of strcmp 

    if(strcmp(ptr->groupName, name)== 0){
        return TRUE;
        // Remove this line as it is unreachable as you are returning
        break;
    }

void addToList(waitListPtr* hd, int size, char* name){

waitListPtr ptr = (waitListPtr) malloc (sizeof(waitList));

strcpy(ptr->groupName, name);

ptr->groupSize = size;

if (*hd == NULL)
{
   ptr->next = NULL;
} else {
    ptr->next = *hd;
}
    *hd = ptr;
}