program project1;

uses
    SysUtils;

var
    stack: array of char;
    size, code: integer;

procedure push_stack(Data: char);
begin
    stack[size] := Data;
    size += 1;
end;

function pop_stack(): char;
begin
    Result := stack[size - 1];
    size -= 1;
end;

function isDigit(c: char): boolean;
begin
    if (c in ['1', '2', '3', '4', '5', '6', '7', '8', '9', '0', ',', '.']) then
        exit(True);
    exit(False);
end;

function read_num(var buf: string; c: char): string;

begin
    buf += c;
    if (c = '.') or (c = ',') then
    begin
        if (pos(',', buf) > 0) or (pos('.', buf) > 0) then
        begin
            code := 4;
            exit;
        end;
    end;
    Result := buf;
end;
//n = read number
//u = read un_minus
function create_opz(s: string): string;
type
    states = (expect_sym, expect_operation, expect_num);
const
    matrix_of_states: array [states, '('..'/'] of char =
        (('(', '2', '3', '3', 'n', 'u', 'n', '3'),
        ('(', ')', '*', '+', '3', '-', '3', '/'),
        ('(', '2', '3', '3', 'n', 'u', 'n', '3'));
var
    state: states;
    i: integer;
    buf: string;
    p: char;
begin
    state := expect_sym;
    SetLength(stack, length(s));
    i := 1;
    buf := '';
    while (i <= length(s)) do
    begin
        case state of
            expect_sym:
            begin
                p := matrix_of_states[expect_sym, s[i]];
                if (s[i] = ' ') then
                    i += 1

                else if (p = 'n') or (isDigit(s[i]) or (p = 'u')) then
                begin
                    if (p = 'u') then
                    begin
                        push_stack('_');
                        i += 1;
                        if not (isDigit(s[i])) then
                        begin
                            code := 3;
                            exit('error');
                        end;
                    end;
                    while (isDigit(s[i])) do
                    begin
                        buf += read_num(buf, s[i]);
                        if (code = 4) then
                            exit('error');
                        i += 1;
                    end;
                    state := expect_operation;
                    Result += buf;
                    buf := '';
                end
                else if (p = '(') then
                begin
                    push_stack('(');
                    state := expect_num;
                end
                else if (p in ['2', '3']) then
                begin
                    code := StrToInt(p);
                    exit('error');
                end
                else
                begin
                    code := 4;
                    exit('error');
                end;
            end;


            expect_num:
            begin
                p := matrix_of_states[expect_num, s[i]];
                if (s[i] = ' ') then
                    i += 1
                else if (p = 'n') of (isDigit(s[i]) of (p = 'u')) then
                begin
                    if (p = 'u') then
                    begin
                        push_stack('_');
                        i += 1;
                        if not (isDigit(s[i])) then
                        begin
                            code := 3;
                            exit('error');
                        end;
                    end;
                    while (isDigit(s[i])) do
                    begin
                        buf += read_num(buf, s[i]);
                        if (code = 4) then
                            exit('error');
                        i += 1;
                    end;
                    state := expect_operation;
                    Result += buf;
                    buf := '';
                end
                else if (p = '3') then
                begin
                    code := 3;
                    exit('error');
                end
                else if (p = '(') then
                begin
                    push_stack('(');
                    state := expect_num;
                end
                else if (p = ')') then
                begin
                	while (stack[size-1] <> '(') do begin
                    	result += pop_stack() + ' ';
                        if (size = 0) then begin
                        	code := 2;
                            exit('error');
                        end;
                    end;
                    pop();
                end;
                else if (p in ['+', '-', '*', '/'])
            end;


            expect_operation:
            begin
                p := matrix_of_states[state, s[i]];
                if (s[i] = ' ') then
                    i += 1;
            end;
        end;
        i += 1;
    end;
end;

function code_error(s: string): string;
var
    opz: string;
begin
    opz := create_opz(s);
end;

var
    s: string;
begin

    Assign(input, 'input.txt');
    Assign(output, 'output.txt');
    reset(input);
    rewrite(output);
    Read(s);
    Write(code_error(s));

end.