156481 05:59:07 7 Mar 2002
Bozhang,HIT,P.R.China 1136 Pascal Accepted 0.09 sec 147K
type BTnode = record
v:word;
l,r:word;
used:boolean;
end;
var
mt:array[1..3000] of BTnode;
a:array[1..3000] of word;
i,n:word;
function FindNullNode(st,en:word):word;
var i:word;
begin
for i:=st to en do if not mt[i].used then break;
if i<=en then result:=i else result:=0;
end;
procedure MakeTree(c,d,p:word);
var i:word;
begin
if c>d then exit;
mt[p].used:=true;
mt[p].v:=a[d];
if c=d then exit;
//l
for i:=c to d-1 do if a[i]>a[d] then break;
if i<>c then begin
mt[p].l:=FindNullNode(1,3000);
MakeTree(c,i-1,mt[p].l);
end;
for i:=d-1 downto c do if a[i]<a[d] then break;
if i<>d-1 then begin
mt[p].r:=FindNullNode(1,3000);
MakeTree(i+1,d-1,mt[p].r);
end;
end;
procedure PrintIt(c:word);
begin
with mt[c] do begin
if r<>0 then PrintIt(r);
if l<>0 then PrintIt(l);
write(v,' ');
end;
end;
begin
fillchar(mt,sizeof(mt),0);
readln(n);
for i:=1 to n do begin
while eoln(input) do readln;
read(a[i]);
end;
MakeTree(1,n,1);
PrintIt(1);
end.