Problem:
Score : 100 points

Problem Statement

An uppercase or lowercase English letter \alpha will be given as input.
If \alpha is uppercase, print A; if it is lowercase, print a.

Constraints

\alpha is an uppercase (A - Z) or lowercase (a - z) English letter.

Input

Input is given from Standard Input in the following format:

α

Output

If \alpha is uppercase, print A; if it is lowercase, print a.

Sample Input 1

B

Sample Output 1

A

B is uppercase, so we should print A.

Sample Input 2

a

Sample Output 2

a

a is lowercase, so we should print a.

Solution in Rust (1.42.0) (judge verdict: Accepted)

use input::Input;

fn main() {
    let mut input = Input::default();

    let a = input.parse();
    let ans = match a {
        'A'..='Z' => 'A',
        _ => 'a',
    };
    println!("{}", ans);
}

#[allow(dead_code)]
pub mod input {
    #[derive(Default)]
    pub struct Input(Vec<String>);

    impl Input {
        pub fn read_line(&mut self) -> String {
            let mut s = String::new();
            std::io::stdin().read_line(&mut s).ok().expect("read error");
            s
        }
        pub fn parse<T: std::str::FromStr>(&mut self) -> T {
            let x = if let Some(x) = self.0.pop() {
                x
            } else {
                let s = self.read_line();
                self.0 = s.split_whitespace().map(String::from).rev().collect();
                self.0.pop().expect("reached EOF")
            };
            x.parse().ok().expect("parse error")
        }
    }
}