POJ/2568.pas

   1 var
   2   data,father,son:array [0..100] of longint;
   3   flag:array [0..100] of boolean;
   4   n,i,p:longint;
   5
   6 procedure dfs(root:longint);
   7 var
   8   i:longint;
   9
  10 begin
  11   if root=0 then exit;
  12   write('(',root);
  13   for i:=1 to n do
  14     if father[i]=root then
  15       begin
  16         write(' ');
  17         dfs(i);
  18       end;
  19   write(')');
  20 end;
  21
  22 begin
  23   while not eof do
  24     begin
  25       n:=1;
  26       while not eoln do
  27         begin
  28           read(data[n]);
  29           inc(son[data[n]]);
  30           inc(n);
  31         end;
  32       readln;
  33       fillchar(father,sizeof(father),0);
  34       fillchar(flag,sizeof(flag),false);
  35       p:=0;
  36       for i:=1 to n-1 do
  37         begin
  38           for p:=1 to n do
  39             if (father[p]=0) and (son[p]=0) then break;
  40           dec(son[data[i]]);
  41           father[p]:=data[i];
  42         end;
  43       dfs(n);
  44       writeln;
  45     end;
  46 end.