Background

Description

Given a string, return a string length 1 from its front, unless front is false, in which case return a string length 1 from its back. The string will be non-empty.

Format

Input

Output

Samples

Hello" tru

"H"

Hello" fals

"o"

oh" tru

"o"

Limitation

1s, 1024KiB for each test case.