void push(int data)
{
NodeL new_node = new NodeL(data);
new_node.next = head;
head = new_node;
}
void PrintList(NodeL headRef)
{
while (headRef != null)
{
Console.WriteLine(headRef.val + "");
headRef = headRef.next;
}
}
private NodeL getMiddle(NodeL h)
{
if (h == null)
{
return(h);
}
NodeL fastptr = h.next;
NodeL slowptr = h;
while (fastptr != null)
{
fastptr = fastptr.next;
if (fastptr != null)
{
slowptr = slowptr.next;
fastptr = fastptr.next;
}
}
return(slowptr);
}
public NodeL PerformMergeSort(NodeL h)
{
if (h == null || h.next == null)
{
return(h);
}
//get middle of the list
NodeL middle = getMiddle(h);
NodeL nextmiddle = middle.next;
middle.next = null;
//mergesort on the left side
NodeL left = PerformMergeSort(h);
NodeL right = PerformMergeSort(nextmiddle);
NodeL sortedList = sortedMerge(left, right);
return(sortedList);
}
NodeL sortedMerge(NodeL a, NodeL b)
{
NodeL result = null;
if (a == null)
{
return(b);
}
if (b == null)
{
return(a);
}
if (a.val < b.val)
{
result = a;
result.next = sortedMerge(a.next, b);
}
else
{
result = b;
result.next = sortedMerge(a, b.next);
}
return(result);
}
public void Insert()
{
Nodehs tg = new Nodehs();
tg.hs = new HocSinh(); tg.link = null;
//??Kiem tra ma lop da co chua? Neu chua=> bao loi; neu co: 1 ghi them SV vao tep hocsinh.txt; cap nhat siso tep Lop.txt?
//TT HS hop le thi them vao DS HS va ghi vao tep
Nodehs tghs = new Nodehs();
danhsachlop dsl = new danhsachlop(); dsl.doctep();
NodeL tgl = new NodeL();
int mahs; string malop;
bool ok1;
bool ok2;//SV có mã lớp chưa có
do
{
ok1 = true;
Console.Write("Nhap Ma hoc sinh: ");
mahs = int.Parse(Console.ReadLine());
tghs = this.ds;
while (tghs != null)//XL
{
if (tghs.hs.mahs == mahs)
{
ok1 = false;
}
tghs = tghs.link;
}
if (!ok1)
{
Console.WriteLine("DL ko hop le: Ma HS da co! Moi nhap lai");
}
} while (!ok1);
tg.hs.mahs = mahs;
tg.hs.nhap1();
do
{
ok2 = false;
Console.Write("Nhap ma lop: ");
malop = Console.ReadLine();
tgl = dsl.ds;
while (tgl != null)
{
if (string.Compare(tgl.L.malop, malop) == 0)
{
ok2 = true; break;
}
tgl = tgl.link;
}
if (!ok2)
{
Console.WriteLine("DL ko hop le: Ma lop chua co! Moi nhap lai");
}
} while (!ok2);//XL
tg.hs.malop = String.Copy(malop);
ghitep(tg);
//Cap nhat si so tep Lop.txt
tg.link = ds;
ds = tg;
}
