Prac_mM

uses UStack;

procedure Inp(var somestack: Stack);
var
    ifp: Text;
    symb: Char;
begin
    assign(ifp, 'input.txt');
    reset(ifp);
    read(ifp, symb);
    while (symb <> '.') do
    begin
        somestack.push(symb);
        read(ifp, symb);
    end;
    close(ifp);
end;

procedure minmax(var tmp: Stack);
var
    op1, op2: char;
    null, operation: char;
begin
    operation:= tmp.pop;
    null:= tmp.pop;
    op1:= tmp.pop;
    null:= tmp.pop;
    op2:= tmp.pop;
    null:= tmp.pop;

    case (operation) of
        'm': begin
                 if (op1 < op2) then
                    tmp.push(op1)
                 else
                    tmp.push(op2);
             end;
        'M': begin
                 if (op1 < op2) then
                    tmp.push(op2)
                else
                    tmp.push(op1);
             end;
    end;
end;



procedure Outp(somestack: Stack);
var
    tmp: Stack;
    symb: char;
    ofp: Text;
begin
    tmp.Init;
    while not (somestack.isEmpty) do
    begin
        symb:= somestack.pop;
        case (symb) of
            ')','(',',','0'..'9': tmp.push(symb);
            'm','M': begin
                        tmp.push(symb);
                        minmax(tmp);
                     end;
        end;
    end;

    assign(ofp, 'output.txt');
    rewrite(ofp);
    writeln(ofp, tmp.top);
    close(ofp);
end;

var
    mystack: Stack;
begin
    mystack.Init;
    Inp(mystack);
    Outp(mystack);
end.