Notes

Template in C

Constraints

2 ≤ the number of operands in the expression ≤ 100
1 ≤ the number of operators in the expression ≤ 99
-1 × 109 ≤ values in the stack ≤ 109

Input

An expression is given in a line. Two consequtive symbols (operand or operator) are separated by a space character.

You can assume that +, - and * are given as the operator and an operand is a positive integer less than 106

Output

Print the computational result in a line.

Examples

Input

1 2 +


Output

3


Input

1 2 + 3 4 - *


Output

-3
import java.util.ArrayDeque;
import java.util.Deque;
import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		 Deque<Integer> stack = new ArrayDeque<Integer>();
		 int result=0;
		 while(scanner.hasNext()) {
		while (scanner.hasNextInt()) {
			stack.push(scanner.nextInt());
		}
		int num1=stack.remove();
		int num2=stack.remove();
		String operate=scanner.next();
		if(operate.equals("+")) {
			result=num2+num1;
		}else if(operate.equals("-")) {
			result=num2-num1;
		}else if(operate.equals("*")) {
			result=num2*num1;
		}
		stack.push(result);
		 }
		 System.out.println(result);
	}

}
