queue_linklist_sinh vien(bassic)

#include <iostream>
#include <string>
using namespace std;
struct sinhvien
{
	int MSSV;
	string HoTen;
	string lop;
	float DTB;
};
struct Node
{
	sinhvien Data;
	Node *next;
};
struct Queue// dinh nghia cau truc cua queue
{
	Node *dau, *cuoi;// Node dau va node cuoi
	int count;// dem so phan tu
};
Node *CreateNode(sinhvien x);
void taoQueue(Queue &q);
bool ktQueueRong(Queue q);
void pushQueue(Queue &q, sinhvien x);
int peakQueue(Queue &q, sinhvien &x);
int popQueue(Queue &q, sinhvien &x);
void input(Queue &q, sinhvien &x, int &n);
void output(Queue q, sinhvien x, int n);
Node *CreateNode(sinhvien x)
{
	Node *p = new Node;
	if (p == NULL)
	{
		return NULL;
	}
	else
	{
		p->Data = x;
		p->next = NULL;
	}
	return p;
}
void taoQueue(Queue &q)// khoi tao queue
{
	q.dau = q.cuoi = NULL;
	q.count = 0;
}
bool ktQueueRong(Queue q)// kiem tra rong
{
	if (q.count == 0)
		return true;
	else
		return false;
}
void pushQueue(Queue &q, sinhvien x)// them phan tu vao queue
{
	Node *p = CreateNode(x);
	if (ktQueueRong(q))
	{
		q.dau = q.cuoi = p;
	}
	else
	{
		q.cuoi->next = p;
		q.cuoi = p;
	}
	q.count++;
}
int peakQueue(Queue &q,sinhvien &x)// lay phan tu nhung khong xoa
{
	if (ktQueueRong(q))
	{
		cout << "hang doi rong";
		return 0;
	}
	else
	{
		sinhvien x = q.dau->Data;
		cout << "MSSV la: " << x.MSSV << endl;
		cout << "ten sinh vien la: " << x.HoTen<< endl;
		cout << "lop sinh vien la: " << x.lop << endl;
		cout << "DTB cua sinh vien la: " << x.DTB<< endl;
		return 1;
	}
}
int popQueue(Queue &q,sinhvien &x)// loai bo phan tu dau khoi hang doi
{
	if (ktQueueRong(q))
	{
		cout << "hang doi rong";
		return 0;
	}
	else
	{
		sinhvien x = q.dau->Data;
		if (q.count == 1)//
			taoQueue(q);
		else
			q.dau = q.dau->next;
		q.count--;
		return 1;
	}
}
void input(Queue &q, sinhvien &x, int &n)
{

	cout << "nhap so luong sinh vien ma ban muon: ";
	cin >> n;
	for (int i = 0; i < n; i++)
	{
		cout << "__________________nhap sinh vien thu " << i + 1 << ": " << endl;
		rewind(stdin);
		cout << "nhap MSSV: ";
		cin >> x.MSSV;
		rewind(stdin);
		cout << "nhap ten sinh vien: ";
		getline(cin, x.HoTen);
		rewind(stdin);
		cout << "nhap lop sinhvien: ";
		getline(cin, x.lop);
		rewind(stdin);
		cout << "nhap DTB cua sinh vien: ";
		cin >> x.DTB;
		pushQueue(q, x);
	}
}
void output(Queue q,sinhvien x,int n)
{
	Node *p = q.dau;
	while (p != NULL)
	{
		cout << "MSSV la: " << p->Data.MSSV << endl;
		cout << "ten sinh vien la: " << p->Data.HoTen << endl;
		cout << "lop sinh vien la: " << p->Data.lop << endl;
		cout << "DTB cua sinh vien la: " << p->Data.DTB << endl;
		p = p->next;
	}
	cout << "\n";
}
//void sapxeptangdan(Queue &q)// chua fix duoc :(((
{
	Node *a = q.dau;
	Node *b = q.dau->next;
	do
	{
		do
		{
			if (a->Data.MSSV > b->Data.MSSV)
			{
				int MSSV;
				string HoTen;
				string lop;
				float DTB;
				MSSV = a->Data.MSSV;
				b->Data.MSSV = MSSV;
				HoTen = a->Data.HoTen;
				b->Data.HoTen = HoTen;
				MSSV = a->Data.MSSV;
				b->Data.MSSV = MSSV;
			}
		} while (b->next == NULL);
	} while (a->next->next == NULL);
}//
int main()
{
	sinhvien x, y;
	int n;
	Queue q;
	taoQueue(q);
	input(q, x, n);
	output(q, x,n);
	int lua_chon;
	cout << "Moi Ban Chon Phep Toan Voi DS LKD";
	cout << "\n1: Kiem Tra Queue Rong";
	cout << "\n2: Them Phan Tu Vao Queue";
	cout << "\n3: Lay Gia Tri Dau Queue";
	cout << "\n4: lay va xoa sinh vien";
	cout << "\n5: Xuat Queue";
	cout << "\n6: Thoat";
	do
	{
		cout << "\nBan Chon: ";
		cin >> lua_chon;
		switch (lua_chon)
		{
		case 1:
		{
			if (ktQueueRong(q))
				cout << "Queue rong";
			else
				cout << "Queue Khong Rong";
			break;
		}
		case 2:
		{
			cout << "nhap phan tu can chen vao Queue: ";
			rewind(stdin);
			cout << "nhap MSSV: ";
			cin >> y.MSSV;
			rewind(stdin);
			cout << "nhap ten sinh vien: ";
			getline(cin, y.HoTen);
			rewind(stdin);
			cout << "nhap lop sinhvien: ";
			getline(cin, y.lop);
			rewind(stdin);
			cout << "nhap DTB cua sinh vien: ";
			cin >> y.DTB;
			pushQueue(q, y);
			break;
		}
		case 3:
		{
			peakQueue(q, x);
			break;
		}
		case 4:
		{
			popQueue(q, x);
			break;
		}
		case 5:
		{
			output(q, x, n);
			break;
		}
		}
	} while (lua_chon != 6);
	return 0;
	system("pause");
}