import java.util.Stack;
import java.util.Vector;

public class OP{
    static void printStack(Stack st){
	for(int i=0; i<st.size(); i++)
	    System.out.print("["+ st.get(i) +"]");
	System.out.println();
    }

    static double add(double a, double b){
	return b+a;
    }
    static double sub(double a, double b){
	return b-a;
    }
    static double mlt(double a, double b){
	return b*a;
    }
    static double div(double a, double b){
	if (a!=0)
	    return b/a;
	else
	    System.exit(1);
	return 0;
    }

    static double getDouble(Object o){
	return Double.parseDouble(o.toString());
    }

    static int pri(String s){
	char c = s.charAt(0);
	switch(c){
	case '+':
	case '-':
	    return 1;
	case '*':
	case '/':
	    return 2;
	}
	return 0;
    }

    static double examine(String exp){
	Stack stack = new Stack();
	String strArr[] = exp.split(" ");

	for (int i=0; i<strArr.length; i++){
	    if(strArr[i].equals("+")){
		stack.push(add(getDouble(stack.pop()), getDouble(stack.pop())));
	    }else if(strArr[i].equals("-")){
		stack.push(sub(getDouble(stack.pop()), getDouble(stack.pop())));
	    }else if(strArr[i].equals("*")){
		stack.push(mlt(getDouble(stack.pop()), getDouble(stack.pop())));
	    }else if(strArr[i].equals("/")){
		stack.push(div(getDouble(stack.pop()), getDouble(stack.pop())));
	    }else{
		stack.push(strArr[i]);
	    }
	}
	return getDouble(stack.pop());
    }

    static String pre(String in){
	Stack stack = new Stack();
	String inArr[] = in.split(" ");
	String out="";

	for (int i=0; i<inArr.length; i++){
	    if (inArr[i].equals("(")){
		stack.push("(");
	    }else if (inArr[i].equals(")")){
		while(true){
		    if(stack.empty()){
			System.out.println("Parentheses mismatch!");
			System.exit(1);
		    }
		    String opp = stack.pop().toString();
		    if(opp.equals("("))
			break;
		    else
			out += opp+" ";
		}
		if(!stack.empty())
		    out += stack.pop().toString()+" ";
	    }else if(inArr[i].equals("+")){
		while(stack.size() > 0 && pri("+") <= pri(stack.get(stack.size()-1).toString()))
		    out+=stack.pop().toString()+" ";
		stack.push("+");
	    }else if(inArr[i].equals("-")){
		while(stack.size() > 0 && pri("-") <= pri(stack.get(stack.size()-1).toString()))
		    out+=stack.pop().toString()+" ";
		stack.push("-");
	    }else if(inArr[i].equals("*")){
		while(stack.size() > 0 && pri("*") <= pri(stack.get(stack.size()-1).toString()))
		    out+=stack.pop().toString()+" ";
		stack.push("*");
	    }else if(inArr[i].equals("/")){
		while(stack.size() > 0 && pri("/") <= pri(stack.get(stack.size()-1).toString()))
		    out+=stack.pop().toString()+" ";
		stack.push("/");
	    }else{
		out+=inArr[i]+" ";
	    }
	}

	while(!stack.empty()){
	    String opp = stack.pop().toString();
	    if(opp.equals("(")){
		System.out.println("Parentheses mismatch!");
		System.exit(1);
	    }
	    out+=opp+" ";
	}
	return out;
    }

    public static void main(String args[]){
	Stack stack = new Stack();
	String exp = "( 56 + 3 ) * 2 / 2 * 42 / ( 2 * ( 2 ) + 3 ) - 194";
	String out = pre(exp);
	System.out.println(exp);
	System.out.println(out);
	System.out.println(examine(out));
    }
}