안녕하세요. 링크드리스트 관련 질문 드립니다...

#include <iostream>
#include <fstream>
#include <string>
#include <sstream>
#include <vector>
#include <cstring>
#include <cstdlib>
 
using namespace std;
 
ifstream inputfile;
ofstream outputfile;
 
class DNode {		
private:
	string name;	
	int score;
	int tot;
	int lowcnt;
	int highcnt;
	DNode* prev;				
	DNode* next;				
	friend class DLinkedList;			
};
 
class DLinkedList {				
public:
	DLinkedList();				
	~DLinkedList();				
	bool empty() const;			
	void remove(const string& name, const int& score);
	void removeFront();		
	DNode* findposition(const string& name,const int& point);
	void add(const string& name, const int& score);
	void print();
	void frontprint();
	void backprint();
private:					
	DNode* header;				
	DNode* trailer;
};
 
bool DLinkedList::empty() const		
{
	return (header->next == trailer);
}
 
DLinkedList::DLinkedList() {		
	header = new DNode;
	trailer = new DNode;
	header->next = trailer;			
	trailer->prev = header;
}
 
DLinkedList::~DLinkedList() {			
	while (!empty()) removeFront();		
	delete header;				
	delete trailer;
}
 
DNode* DLinkedList::findposition(const string& name,const int& point) { // 입력된 점수가 header다음 노드부터 시작하여 그 노드보다 더 낮으면 다음 노드를 다시 비교, 그렇게해서 다음 노드보다 더 높은 스코어면 마지막에 비교한 노드를 반환,처음엔 헤더의 다음인 꼬리의 score(=0)을 비교하므로 해더와 꼬리의 중간에 값이 들어가게 됨.
	DNode* fp =  header;
	while (1) {
		fp = fp->next;
		if ((fp->score) < point) {
			return fp;
		}
		else if (fp->score == point) {
			if (fp == trailer)
				return fp;
			if ((name.compare((fp->name)) == -1) || (name.compare((fp->name)) == 0))
				return fp;
		}
	}
}
 
void DLinkedList::add(const string& name, const int& point) {
	DNode* u = new DNode;
	trailer->score = 0;
	u->tot = 0;
	u->highcnt = 0;
	u->lowcnt = 0;
	u->name = name;		
	u->score = point;
	//findposition(name, score)//여기서 add 시킬 위치가 나옴.(findpo)의 앞에 add하면됨.
	DNode* x = 	findposition(name, point);//findposi는 DNode 주소값을 반환함.
 
	u->next = x;
	u->prev = x->prev;
	x->prev->next = x->prev = u;
}
 
void DLinkedList::remove(const string& name, const int& point) {
	int k = 0;
	DNode* ex = header;
	while (ex!=trailer) {
		DNode* ex = header;
		for(int i =0 ; i<=k;i++)
			ex = ex->next;
		if (ex == trailer)
			break;
		if (ex->score == point) {
			if ((ex->name).compare(name) == 0) {
				DNode* u = ex->prev;
				DNode* w = ex->next;
				u->next = w;
				w->prev = u;
				k++;
				delete ex;
			}
		}
	}
}
 
void DLinkedList::removeFront()		
{
	remove(header->next->name,header->next->score);
}
 
void DLinkedList::print()
{
	DNode* u = header->next;
	while (1) {
		if (u == trailer)
			break;
		u->tot = (u->prev->tot) + 1;
 
		trailer->tot = (trailer->prev->tot) + 1;
 
		if ((u->score) != (u->prev->score))
			u->highcnt = (u->tot);
		else
			u->highcnt = (u->prev->highcnt);
		u = u->next;
	}
 
	DNode* w = trailer->prev; //이 방법은 10명이 모두 같은 점수면 low일때 모두 10등으로 나올듯. QnA에 따르면 뒤에서부터 줄이는게 맞을듯.
	while (1) {
		if (w == header)
			break;
		if ((w->score) != (w->next->score))
			w->lowcnt = w->tot;
		else
			if (w->next = trailer)
				w->lowcnt = trailer->tot - 1;
			else if (w->next != trailer)
				w->lowcnt = w->next->lowcnt;
		w = w->prev;
	}
	frontprint();
	outputfile << endl;
	backprint();
	outputfile << endl;
}
 
void DLinkedList::frontprint()
{
	DNode* f = header->next;
	for (int i = 0; i < 10;i++) {
		if (f == trailer)
			break;
		outputfile << f->highcnt << "\t" << f->name << "\t" << f->score << endl;
		f = f->next;
	}
}
 
void DLinkedList::backprint()
{
	DNode* b =  trailer->prev;
	for (int i = 0; i < 10;i++) {
		if (b == header)
			break;
		outputfile << b->lowcnt << "\t" << b->name << "\t" << b->score << endl;
		b = b->prev;
	}
}
 
int main (int argc, char* argv[]){
 
	if(argc < 3) {
		cout <<"Usage: " << argv[0] << "inputfile output_file" <<endl; 
	}
 
	inputfile.open(argv[1]);
	if(inputfile.fail()) 
		cout << "Cannot open inpufile" <<endl;
 
	outputfile.open(argv[2]);
	if(outputfile.fail()) 
		cout << "Cannot open outputfile" << endl;
 
 
	if(inputfile.is_open()) {
		string line;
		DLinkedList dll;
		string name;
		int point;
		char type;
 
		while (getline(inputfile, line)) {
			istringstream iss(line);
			iss >> type >> name >> point;
			if(type == 'a')
				dll.add(name, point);
			else if (type == 'r')
				dll.remove(name, point);
			else if (type == 'p')
				dll.print();		
		}
	}
	inputfile.close();
	outputfile.close();
	return 0;
}