Question

I am writing a C++ linked list class. I have implemented and tested insert and print. However, I can’t seem to return a Node pointer for delete. I get these errors when I try delete:

    Node.h:11: error: expected unqualified-id before "delete"
    Node.h:11: error: abstract declarator `Node*' used as declaration
    Node.h:11: error: expected `;' before "delete"

    Node.cpp:21: error: expected unqualified-id before "delete"
    Node.cpp:21: error: expected init-declarator before "delete"
    Node.cpp:21: error: expected `,' or `;' before "delete"

    make.exe: *** [Node.o] Error 1

    Execution terminated

Here’s my code:

Node.h

    #ifndef Node_H
    #define Node_H


    class Node{
          int data;
          Node* next;

    public:
           Node(int data);       
           void insert(int d);
           Node* delete(int d);
           void printOut(void);
    };

    #endif

Node.cpp

    #include <stdio.h>
    #include "Node.h"

    Node::Node(int d){
          data = d;
          next = NULL;
          }

    void Node::insert(int d){

          Node* n = this;
          Node* current = new Node(d);

          while(n->next != NULL){
                  n = n->next;                   
                  }

          n->next = current;
          }

    Node* Node::delete(int d){

          Node* head = this;
          Node* n = this;

          if (n->data = null){
             return n;
             }

          if (n->data == d){
             return n->next;
             }

          while(n->next != NULL){

          if (n->next->data == d){
             n->next = n->next->next;
             return head;
             }

          n = n->next;

          }

        return head;

        }

    void Node::printOut(void){

         Node* n = this;

         while(n->next != NULL){
                      printf("%d ->", n->data);
                       n = n->next;                   
                       }

         printf("%d \n", n->data);

         }

main:

    #include <iostream>
    #include <stdio.h>
    #include <cstdlib>

    #include "Node.h"
    using namespace std;

    int main (void){
        int i = 0;

        Node* root = new Node(111);
        Node* result;

        for (i = 0; i < 9; i++){
            root->insert(i);
            } 

        root->printOut();

        result = root->delete(5);

        result->printOut();

        printf("Hello j \n");

        getchar();
        delete[] root; 
        return 0;   
    }

Answer 1

The token delete is a reserved keyword in C++. Pick a different name for the function (like remove).