var PointerType : collection of
    record
        Data : string (40)
        Next : pointer to PointerType
        Prev : pointer to PointerType
    end record
var Backup : collection of
    record
        Data : string (40)
        Next : pointer to Backup
        Prev : pointer to Backup
    end record
%------------------- procedure---------------------------------------

procedure First (var InsertRecord, ListStart, ListEnd : pointer to PointerType, spNames : string)
    new InsertRecord
    ListEnd := InsertRecord
    ^InsertRecord.Next := nil
    ^InsertRecord.Data := spNames
    ListStart := InsertRecord
end First
procedure bFirst (var bIRecord, bListStart, bListEnd : pointer to Backup, spNames : string)
    new bIRecord
    bListEnd := bIRecord
    ^bIRecord.Next := nil
    ^bIRecord.Data := spNames
    bListStart := bIRecord
end bFirst
procedure InName (var InsertRecord, ListStart, ListEnd : pointer to PointerType, spName : string, var ipAm : int)
    new InsertRecord
    ^InsertRecord.Next := ListStart
    ^ListStart.Prev := InsertRecord
    ^InsertRecord.Data := spName
    ListStart := InsertRecord
    ipAm += 1
end InName
procedure bInName (var bIRecord, bListStart, bListEnd : pointer to Backup, spName : string)
    new bIRecord
    ^bIRecord.Next := bListStart
    ^bListStart.Prev := bIRecord
    ^bIRecord.Data := spName
    bListStart := bIRecord
end bInName
procedure Circular (var InsertRecord, ListStart, ListEnd : pointer to PointerType)
    InsertRecord := ListEnd
end Circular
procedure OutName (ListEnd : pointer to PointerType, ipAm : int)
    var i : int := 0
    var TempList := ListEnd
    loop
        i += 1
        put ^TempList.Data
        exit when i = ipAm
        TempList := ^TempList.Prev
    end loop
end OutName
procedure bOutName (bListEnd : pointer to Backup, ipAm : int)
    var i : int := 0
    var TempList := bListEnd
    loop
        i += 1
        put ^TempList.Data
        exit when i = ipAm
        TempList := ^TempList.Prev
    end loop
end bOutName
%----------------------- main----------------------------------------
var InsertRecord, ListStart, ListEnd : pointer to PointerType
var bIRecord, bListStart, bListEnd : pointer to Backup
var sNames : string
var iAm : int := 1
var iAm2 : int := 1
put "Input the name of a contestant"
get sNames : *
First (InsertRecord, ListStart, ListEnd, sNames)
bFirst (bIRecord, bListStart, bListEnd, sNames)
if (sNames = 'Fin') or (sNames = 'fin') then
    %nothing
else
    loop
        put "Input the name of a contestant"
        get sNames : *
        exit when (sNames = 'fin') or (sNames = 'Fin')
        InName (InsertRecord, ListStart, ListEnd, sNames, iAm)
        bInName (bIRecord, bListStart, bListEnd, sNames)
    end loop
end if
Circular (InsertRecord, ListStart, ListEnd)
cls
iAm2 := iAm
put "List: "
OutName (ListEnd, iAm)
put "Which Contestant do you want to elliminate?"
get sNames
%delete
put "Backup : "
bOutName (bListEnd, iAm2)
put "Remaining: "
OutName(ListEnd, iAm)