Monkey Smile Check

Background

Dawei and Xiaoxiao are observing two cute monkeys at the zoo. They noticed that interesting things happen when both monkeys are happily smiling, or when both monkeys are gloomy and not smiling.

Problem Description

We have two monkeys, $a$ and $b$. The parameters $aSmile$ and $bSmile$ indicate if monkey $a$ and monkey $b$ are smiling, respectively. We are in trouble if both monkeys are smiling or if neither of them is smiling. Return true if we are in trouble.

Input Format

The input is given from standard input in the following format.

aSmile (A boolean value, indicating if monkey $a$ is smiling) bSmile (A boolean value, indicating if monkey $b$ is smiling)

Output Format

The output should be printed to standard output in the following format.

A boolean value, indicating if we are in trouble.

Sample

true true

true

false false

true

true false

false

Sample Explanation

Sample 1: Both monkeys are smiling (true true), which meets the condition "both monkeys are smiling\