import java.util.Stack;

public class Source {
    public static void main(String[] args) {

    }

    static String infix_to_reverse_polish(String infix) {
        final String ops = "=|&?<>-+/*^!~()";
        StringBuilder sb = new StringBuilder();
        Stack<Integer> s = new Stack<>();
        for (int i = 0; i < infix.length(); i++) {
            String current = new String("" + infix.charAt(i));
            System.out.println(current);
            if (current.isEmpty())
                continue;
            char c = current.charAt(0);
            int idx = ops.indexOf(c);

            if (idx != -1) {
                if (s.isEmpty())
                    s.push(idx);

                else {
                    while (!s.isEmpty()) {
                        int prec2 = s.peek();
                        int prec1 = idx ;
                        if (prec2 > prec1 || (prec2 == prec1 && c != '^' && c != '!' && c != '~'))
                            sb.append(ops.charAt(s.pop())).append(' ');
                        else break;
                    }
                    s.push(idx);
                }
            }
            else if (c == '(') {
                s.push(-2);
            }
            else if (c == ')') {
                if(s.size() == 0) {
                    return "e r r o r";
                }
                while (s.peek() != -2)
                    sb.append(ops.charAt(s.pop())).append(' ');
                s.pop();
            }
            else {
                sb.append(current).append(' ');
            }
        }
        while (!s.isEmpty())
            sb.append(ops.charAt(s.pop())).append(' ');
        return sb.toString();
    }

}