将不同的单词保存到链表中

基本上我在这里有2个链表:列表和不同。 有一些单词已经保存在“list”结构中。 是否会写一个程序,它会找到不同/独特的单词并将其保存到’distinct’结构中。 这是我到目前为止根据指针的概念得到的。 然而,当我尝试打印’distinct’时,程序崩溃了:(如果我错了,请纠正我。

struct list { char string[50]; struct list *next; }; struct distinct { char string[50]; struct distinct *next; }; void checkdistinct() { list *ori = NULL; distinct *copy = NULL; distinct *check = NULL; if(ori == NULL && copy == NULL) { //first time. ori = ori->next; copy = copy->next; copy = (distinct*)malloc(sizeof(distinct)); strcpy(copy->string, ori->string); ori = ori->next; copy = copy->next; } else {} while(ori!=NULL) { check = check->next; while(check != NULL) { if(strcmp(ori->string, check->string)!=0) { check = check->next; } else { ori = ori->next; check = NULL; } } //only compare same casing words, for now. copy = (distinct*)malloc(sizeof(distinct)); strcpy(copy->string, ori->string); ori = ori->next; copy = copy->next; } } 

当我尝试在main中打印时,它会崩溃:(如果您需要额外的代码注释,请回复。谢谢!

这三行是一个可能的罪魁祸首:

 if(ori == NULL && copy == NULL) { //first time. ori = ori->next; copy = copy->next; 

在这里检查oricopy是否为NULL ,然后立即取消引用那些NULL指针!

在您的代码中,distinct不是变量的名称,而是结构的名称。 你似乎误解了指针,希望这会有所帮助,尽管它与你的问题没有直接关系。

我遗漏了很多错误检查,使代码看起来更简单。

 typedef struct listnode { char string[50]; struct listnode *next; } list_node; typedef struct listbase { list_node *head; int numberOfElements; } list; /* Add a new string at the start of the list */ void ListPrepend(list *myList, char *myString) { list_node *newNode = malloc(sizeof *newNode); /* create node to store string */ strcpy(newNode->string, myString); /* copy string into node */ newNode->next = myList->head; /* New node now followed by whole list */ myList->head = newNode; /* List now starts with new node */ myList->numberOfElements++; } /* Add a new string at the end of the list */ void ListAppend(list *myList, char *myString) { list_node *newNode = malloc(sizeof *newNode), /* create node to store string */ *currentNode = myList->head; /* pointer to node so we can find the end */ strcpy(newNode->string, myString); /* copy string into new node */ newNode->next = NULL; /* Nothing following this node */ if ( myList->head == NULL ) { myList->head = newNode; /* we didn't have a start node so assign it */ } else { /* if there is a next node, move to it */ while ( currentNode->next != NULL ) { currentNode = currentNode->next; } /* there is no next node so add new node on the end */ currentNode->next = newNode; } myList->numberOfElements++; } /* Show the list in order head to tail */ void ListDisplay(list *myList) { list_node *currentNode = myList->head; while ( currentNode != NULL ) { printf("%s\n", currentNode->string); currentNode = currentNode->next; } } int main() { list distinct = {0}; /* Now there is a variable called distinct */ char name[][20] = {"Lim Zheng Yue", "Monkey", "Dave"}; ListAppend(&distinct, name[0]); ListAppend(&distinct, name[1]); ListPrepend(&distinct, name[2]); ListDisplay(&distinct); }