{my wrong code}
const
  maxn=600;
type
  link=^re;
  re=record
    num:integer;
    q:link;
  end;
var
  p:link;
  n:longint;
  va:array[1..maxn]of byte;
  g:array[1..maxn]of link;
  max:array[1..maxn,0..1]of longint;
  r:array[1..maxn]of boolean;

  procedure init;
  var
    x,y,i:longint;
  begin
    assign(input,'1039.in'); reset(Input);
    fillchar(r,sizeof(r),false);
    readln(n);
    for i:=1 to n do
      readln(va[i]);
    readln(y,x);
    while (x<>0) or (y<>0) do
    begin
      r[y]:=true;
      new(p);
      p^.num:=y;
      p^.q:=g[x];
      g[x]:=p;
      readln(y,x);
    end;
  end;

  procedure solve(root:longint);
  var
    p:link;
    x,big:longint;
  begin
    new(p); p:=g[root];
    while p<>nil do
    begin
      x:=p^.num;
      solve(x);
      inc(max[root,1],max[x,0]);
      if max[x,0]>max[x,1]
        then big:=max[x,0]
        else big:=max[x,1];
      inc(max[root,0],big);
      p:=p^.q;
    end;
    inc(max[root,1],va[root]);
  end;

  procedure main;
  var
    i:longint;
  begin
    for i:=1 to n do
      if not(r[i])
        then begin
          solve(i);
          if max[i,1]>max[i,0]
            then writeln(max[i,1])
            else writeln(max[i,0]);
          exit;
        end;
  end;

begin
  init;
  main;
end.


The code is wrong at the fourth test.I am pluzzled.
Please give me some tests. Sorry for my fool.

1). maxn must be 6000
2). va must be array of LongInt

    Thank you very much!
    I fix my code following your advice and AC now.
I am so careless that I feel very ashamed.You are an alive
Lei Feng(a great person).And I would like to make friends
with you.

'An alive Lei Feng' is wrong, it must be 'a living Lei Feng'.