Question

我正在编写一些用户可以输入某些信息的代码;然后被推回到一个链表......除了这个因为这些行在这里有一个额外的0被添加到列表末尾之外，所有这些都是有用的：

用户如何输入信息：

int sizeOf = 0, i = 0, itemStock = 0;//, individualItemCost = 0;
string name;
double individualItemCost = 0;
cout << "How many lines would you like to input: " << endl;
cin >> sizeOf;  

//Create a head node(first element)...
Stock* head = buildNode(name, itemStock, individualItemCost);

//Each time, create a new node and push onto the list...
while (i < sizeOf)
{
    /*cout << "Please enter the students name: " << endl;
    cin >> head->itemName;
    cout << "Please enter the item stock: " << endl;
    cin >> head->itemStock; 
    cout << "Please enter the item price: " << endl;
    cin >> head->individualItemCost;    */

    cout << "Please enter the students name: " << endl;
    cin >> name;
    cout << "Please enter the item stock: " << endl;
    cin >> itemStock;   
    cout << "Please enter the item price: " << endl;
    cin >> individualItemCost;  

    //push(head,head->itemName, head->itemStock, head->individualItemCost);  //Push back everything in head
    push(head,name, itemStock, individualItemCost);  //Push back everything in head
    i++;

}

Buildnode功能：

    Stock* buildNode(string itemName, int itemStock, double individualItemCost)
{
    Stock* s = new Stock;
    s->itemName = itemName;
    s->itemStock = itemStock;
    s->individualItemCost = individualItemCost;
    s->next = nullptr;
    return s;
}

我如何将ti推到列表中：

void push(struct Stock*& list, string itemName, int itemStock, double individualItemCost)
{
    Stock* newnode = new Stock;
    newnode->itemName = itemName;
    newnode->itemStock = itemStock;
    newnode->individualItemCost = individualItemCost;
    newnode->next = list;
    list = newnode;
}

我只需要输入用户输入的内容，而不是头部。

Answer 1

为什么要使用具有head值的节点初始化0？

这样想，启动时，head是null ..

当您的push方法在列表的前面添加新节点时，即使列表中没有任何其他节点，它也会添加一个新节点。你只需要换行

Stock* head = buildNode(name, itemStock, individualItemCost);

到

Stock* head = null;

希望它有所帮助...

防止头节点被推入链表

1 个答案: