single linked list!!!

I am trying to build a bag class with single linked list!!
I tested my code but I think there is something long with connecting the nodes by using pointers!
Anyone see the problems??

Header file!
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#ifndef BAG_H_
#define BAG_H_

#include <iostream>
using std::string;
class bag{
public:
	bag();
	void push_back(bag*& head_ptr, string str);
	bool search(bag*& head_ptr, string target);
	void show(bag*& head_ptr);
	void remove(bag*& head_ptr);

private:
	bag* link;
	string name;
	size_t length;
};



#endif /* BAG_H_ */ 



cpp file!!
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#include "bag.h"
#include <iostream>

using std::string;
using std::cout;
using std::endl;

bag::bag(){
	link = NULL;
	name = "";
	length = 0;
}

void bag::push_back(bag*& head_ptr, string str){
	if(head_ptr == NULL){
		head_ptr = new bag();
		head_ptr->link = NULL;
		head_ptr->name = str;
		head_ptr->length++;
	}
	else{
		bag* temp = NULL;
		temp = head_ptr;
		bool truth = true;
		while(truth){
			if(temp == NULL){
				truth = false;
				break;
			}
			temp = temp->link;
		}
		temp = new bag();
		temp->link = NULL;
		temp->name = str;
		temp->length++;

	}
}

void bag::remove(bag*& head_ptr){

	while(true){
		bag* temp = head_ptr;
		head_ptr = temp->link;
		if(head_ptr == NULL){
			return;
		}
		delete temp;

	}
}

void bag::show(bag*& head_ptr){
	for(bag* cursor = head_ptr; cursor!=NULL; cursor = cursor->link){
		cout<<"name = "<<cursor->name<<"length = "<<cursor->length<<endl;
	}
}
You never link the cells.
When the loop 25 ends, `temp' will be NULL. Immediately you set it to a new allocated object.

What you need to do:
Get to the last cell and do last_cell.link = new node;

It's simpler if you use an empty header cell and a circular list http://www.cplusplus.com/forum/beginner/90716/#msg487820


Also, you may want to distinguish an `element' from a `container'
Last edited on
thank you!!
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