The rucksack problem solution in Pascal

rucksack.pas

program rucksack;
uses math;
type THistory = array [0..10000,0..10000] of integer;
        tItem= record
                val,size:integer;
                end;
     TItems = array [1..10000] of tItem;
var fin,fout: text;
        maxSize,maxItems,curSize,counter,counter2:integer;
        History:THIstory;
        items: TItems;
begin
        assign(fin,'in.txt');
        reset(fin);
        readln(fin, maxSize,maxItems);

        for counter:=1 to maxITEMS do
            readln(fin,items[counter].val,items[counter].size);

        history[maxSize,maxItems]:=-1;

        for counter:=1 to max(maxSize,maxItems) do begin
                history[counter,0]:=0;
                history[0,counter]:=0;
        end;

        counter:=1;

        while (history[maxsize,maxItems]=-1) do begin
                for counter2:=0 to items[counter].size-1 do
                        history[counter2,counter]:=history[counter2,counter-1];

                curSize:=items[counter].size;
                for counter2:=items[counter].size to maxSize do begin
                        history[counter2,counter]:=
                        max(curSize+history[maxSize-curSize,counter-1],
                        history[counter2,counter-1]);
                        writeln(history[counter2,counter]);
                        readln;
                end;
                writeln('############');
                readln;
                inc(counter);
        end;
        writeln(history[maxsize,maxItems]);
        readln;

end.