const
  maxn=100;
var
  a:array[1..maxn,1..maxn] of integer;
  fa:array[1..maxn,1..maxn] of integer;
  s:string[maxn];
  p,q,i,j,k:integer;
procedure sub(x,y:integer);
begin
  case fa[x,y] of
    -1:begin
         write('(');
         if x+1<=y-1 then sub(x+1,y-1);
         write(')');
       end;
    -2:begin
         write('(');
         if x+1<=y then sub(x+1,y);
         write('(');
       end;
    -3:begin
         write('[');
         if x+y<=y-1 then sub(x+1,y-1);
         write(']');
       end;
    -4:begin
         write('[');
         if x+1<=y then sub(x+1,y);
         write(']');
       end;
    -5:begin
         write('(');
         if x<=y-1 then sub(x,y-1);
         write(')');
       end;
    -6:begin
         write('[');
         if x<=y-1 then sub(x,y-1);
         write(']');
       end;
    0:begin
        if (s[x]='(')or(s[x]=')') then write('()') else write('[]');
      end;
    else begin
      sub(x,fa[x,y]);sub(fa[x,y]+1,y);
    end;
  end;
end;

begin
  fillchar(a,sizeof(a),0);
  fillchar(fa,sizeof(fa),0);
  readln(s);
  for p:=1 to length(S) do
    for q:=1 to length(S)-p+1 do begin
      i:=q;j:=q+p-1;
      if i=j then begin
        a[i,i]:=1;
      end else begin

        a[i,j]:=maxint;
        for k:=i to j-1 do
          if a[i,k]+a[k+1,j]<a[i,j] then begin
            a[i,j]:=a[i,k]+a[k+1,j];
            fa[i,j]:=k;
          end;
        if (s[i]='(')and(s[j]=')') then begin
          if a[i+1,j-1]<a[i,j] then begin
            a[i,j]:=a[i+1,j-1];
            fa[i,j]:=-1;
          end
        end else
        if (s[i]='(') then begin
          if a[i+1,j]+1<a[i,j] then begin
            a[i,j]:=a[i+1,j]+1;
            fa[i,j]:=-2;
          end;
        end else
        if (s[i]='[')and(s[j]=']') then begin
          if a[i+1,j-1]<a[i,j] then begin
            a[i,j]:=a[i+1,j-1];
            fa[i,j]:=-3;
          end
        end else
        if (s[i]='[') then begin
          if a[i+1,j]+1<a[i,j] then begin
            a[i,j]:=a[i+1,j]+1;
            fa[i,j]:=-4;
          end;
        end else
        if s[j]=')' then begin
          if a[i,j-1]+1<a[i,j] then begin
            a[i,j]:=a[i,j-1]+1;
            fa[i,j]:=-5;
          end;
        end else
        if s[j]=']' then begin
          if a[i,j-1]+1<a[i,j] then begin
            a[i,j]:=a[i,j-1]+1;
            fa[i,j]:=-6;
          end;
        end;
      end;
    end;
  sub(i,j);
  writeln;
end.