数据结构--单向链表的代码实现(c++)

template 
struct node{
    type val;
    node *next;
    node() {next=NULL;}
    node(type &x,type *p){val=x;next=p;}
};

template 
class list{
    public:
    node *head;//头结点;
    list(){head=new node;}
    int Length();
    bool Empty();
    void Clear();
    void Traverse(void(*visit)(const type &e));
    bool Get_value(int pos,type &e);
    bool Set_value(int pos,type &e);
    bool Insert(int position, const type &x);
    bool Delete(int pos);
    node* get_ptr(int position);
};

template 
int list::Length(){
    int count=0;
    node *temp_ptr;
    for (temp_ptr=head->next;temp_ptr!=NULL;temp_ptr=temp_ptr->next) counr++;
    return count;
}

template 
bool list::Empty(){
    return head->next==NULL;
}

template 
bool list::Empty(){
    return head->next==NULL;
}

template 
void list::Traverse(void (*visit)(const type &e)){
    node *temp_ptr;
    for (temp_ptr=head->next;temp_ptr!=NULL;temp_ptr=temp_ptr->next){
        (*visit)(temp_ptr->val);
    }
}

将位置为pos的元素值赋值给e，如果位置不合理就返回false，合理返回true。

template 
bool list::Get_value(int pos,type &e){
    if (pos<1||pos>Length()) return false;
    node *temp_pos=get_ptr(pos);
    e=temp_pos->val;
    return true;
}

template 
bool list::Set_value(int pos,type &e){
    if (pos<1||pos>Length()) return false;
    node *temp_ptr=Get_ptr(pos);
    temp_ptr->val=e;
    return true;
}

template 
bool list::Insert (int position, const type &x){
    if (pos<1||pos>Length()+1) return false;
    node *temp_ptr=Get_ptr(position-1);
    node *new_ptr=new node(temp_ptr->next,x);
    temp_ptr->next=new_ptr;
    return true;
}

template 
bool list::Delete(int pos){
    if (pos<1||pos>Length()) return false;
    node *pre_pos,*next_pos;
    pre_pos=Get_ptr(pos-1);
    next_pos=Get_ptr(pos);
    pre_pos->next=next_pos->next;
    delete next_pos;
    return true;
}