Charging a binary tree

Question

I'm trying to charge a binary tree in an ascendent form from a file of Integers, but it doesn't works.

program trees;

type 
        fl = file of Integer
    ;   ltree = ^puntTree
    ;   puntTree = record
                val : Integer
            ;   big : ltree
            ; low : ltree
        end
    ;

procedure openFile ( var iFile: fl; name: String; var error: Boolean );
    begin
        error := false;
        assign ( iFile, name );
        {$I-}
            reset ( iFile );
        {$I+}   
        if ( ioResult <> 0 ) then
            error := true;
    end;


procedure loadTree ( var tree: ltree; var iFile: fl; var principalNode: ltree; position: Integer );
    var val
                :Integer
        ;   node
                :ltree
        ;
    begin
        if ( tree = nil ) then
            begin
                seek ( iFile, position );
                read ( iFile, val );
                new ( tree );
                tree^.val := val;
                tree^.low := nil;
                tree^.big := nil;
            end;

        if not eof ( iFile ) then
            begin
                read ( iFile, val );

                node := principalNode;

                while ( node <> nil ) do
                    if ( node^.val < val ) then
                        node := node^.big
                    else
                        node := node^.low;

                cargartree ( node, iFile, principalNode, ( position + 1 ) );
            end;
    end;

procedure printTree ( tree: ltree );
    begin
        if ( tree <> nil ) then
            begin
                printTree ( tree^.low );
                writeln ( tree^.val, ' - ' );
                printTree ( tree^.big );
            end;
    end;

var 
        tree
    ,   principalNode
            :ltree
    ;   iFile
            :fl
    ;   fileName
            :String
    ;   error
            :Boolean
    ;

begin
    readln ( fileName );
    abrirfile ( iFile, fileName, error );
    if not error then
        loadTree ( tree, principalNode, iFile, 0 );
    printTree(principalNode);
end.

This is the code.

The file have 9 elements:

1 5 9 20 58 95 1 3 8

But when I print the tree, the console shows only:

1 - 

There's a way to fix it? Thanks!

Answer 1

After trying to imagine what the code given is supposed to do as opposed to what it actually does, the primary error is that you are passing 'principalnode' to 'printtree'; you should be passing 'tree' to this procedure.