error in node constructor for Linked-list c++

Question

i'm trying to make a LinkedList of ints and for that i created a Node class. but the compiler constantly gives me the same error. i searched all over the web and the answers i found didn't work, or i did not understand them.

the error is the following:
line 51: new types may not be defined in a return type
line 51: return type specification for constructor invalid

all 4 constructors have the same problem, the error in line 51 is just the first one of the four.

here is my Node class with all it has. i didn't copy the getters and setters because they have no errors, and the code is semi-obvious.

thanks a lot. Andy

class Node{

private:
    int val;
    Node* pPrv;
    Node* pNxt;

public:
    Node();
    Node(Node&);
    Node(int);    
    Node(int, Node*, Node*);

    void setVal(int auxVal);
    void setPrv(Node* auxPrv);
    void setNxt(Node* auxNxt);

    int getVal();
    Node* getPrv();
    Node* getNxt();
}

Node::Node(){ //this is line 51
    val = 0;
    pPrv = NULL;
    pNxt = NULL;
}

Node::Node(Node &node2){ //this line has exactly the same error
    val = node2.getVal();
    pPrv = node2.getPrv();
    pNxt = node2.getNxt();
}

Node::Node(int valAux){ //so does this one
    val = valAux;
    pPrv = NULL;
    pNxt = NULL;
}

Node::Node(int valAux, Node* prvAux, Node* nxtAux){ //and also this one
    val = valAux;
    pPrv = prvAux;
    pNxt = nxtAux;
}

You are missing a semicolon ; after your class declaration. — πάντα ῥεῖ
– πάντα ῥεῖ, Commented Nov 13, 2014 at 20:34
By the way, be careful with your copy-constructor. Copying a node can lead to nasty things happening if you remove a node from the list, and you expect the pPrv and pNxt to be valid. If you remove the node pointed to by pNxt, the original will be updated, but the copy will still have its old `pNxt pointer, now pointing to a removed node. — Some programmer dude
– Some programmer dude, Commented Nov 13, 2014 at 20:36
Do you write this list only for exercise? You can use list or deque from standard library. — Piotr Siupa
– Piotr Siupa, Commented Nov 13, 2014 at 20:51

Vlad from Moscow · Accepted Answer · 2014-11-13 20:34:11Z

1

You forgot tp place a semicolon after the class definition.

In this case the compiler considers the declaration of the class above constructor Node()

class Node{
//...
}
Node::Node(){
    val = 0;
    pPrv = NULL;
    pNxt = NULL;
}

as its return type.

answered Nov 13, 2014 at 20:34

Vlad from Moscow

313k27 gold badges204 silver badges358 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

error in node constructor for Linked-list c++

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related