USES CRT; CONST  MaxLength=50;     {do dai danh sach} TYPE Elementtype = Integer;    {kieu phan tu trong DS} Position = Integer;     {kieu vi tri cac phan tu}     List= record {mang chua cac phan tu cua danh sach} Element: Array[1..MaxLength] of Elementtype; Last : Integer; { giu do dai danh sach } End; {------------------------------------------------------------------} Procedure Makenull_List(var L: List); begin      L.Last:=0; end; Function Empty_List(L : List ) : Boolean; Begin      Empty_List:=(L.Last=0); End; {------------------------------------------------------------------} Procedure Insert_List(X:Elementtype; P:Position; var L: List); Var q:Position; Begin      If L.last>=MaxLength Then   Writeln(`Loi : danh sach day `)      Else         If (p>L.Last+1) or (pL.last) or (pL.Last) or (pL.Last+1) or (p...