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type sni = record
s : ansistring;
n : integer
end;
var
f : text;
s : ansistring;
op, cl : integer;
c : char;
function cal(s : ansistring) : integer;
var
c : char;
tmp : integer = 0;
begin
cal := 0;
for c in s do
if c = '(' then
begin
inc(tmp);
if tmp > cal then
cal := tmp
end
else
begin
dec(tmp);
if tmp < 0 then exit(0)
end;
if tmp <> 0 then
exit(0)
end;
function rplc(
s : ansistring;
c : char;
idx : integer
) : ansistring;
begin
exit(copy(s, 1, idx - 1) + c + copy(s, idx + 1, length(s) - idx + 1))
end;
function libtn(
s : ansistring;
op, cl, idx : integer
) : sni;
var
i : integer;
v0, v1 : sni;
begin
if (op = 0) and (cl = 0) then
begin
libtn.s := s;
libtn.n := cal(s);
exit
end;
i := idx;
while s[i] <> '?' do
inc(i);
if op = 0 then
exit(libtn(rplc(s, ')', i), 0, cl - 1, i + 1));
if cl = 0 then
exit(libtn(rplc(s, '(', i), op - 1, 0, i + 1));
v0 := libtn(rplc(s, '(', i), op - 1, cl, i + 1);
v1 := libtn(rplc(s, ')', i), op, cl - 1, i + 1);
if v0.n > v1.n then
exit(v0)
else exit(v1)
end;
begin
assign(f, 'BTN.INP');
reset(f);
read(f, s);
close(f);
op := length(s) div 2;
cl := length(s) div 2;
for c in s do
if c = '(' then
dec(op)
else if c = ')' then
dec(cl);
assign(f, 'BTN.OUT');
rewrite(f);
writeln(f, libtn(s, op, cl, 1).s);
close(f)
end.
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