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: Wrong Answer)

// https://atcoder.jp/contests/abc171/tasks/abc171_a

use proconio::input;

fn main() {
    let lowers = b'a'..b'z';
    input! {
      a: String
    }
    for c in a.as_str().chars() {
        println!(
            "{}",
            if lowers.contains(&(c as u8)) {
                "a"
            } else {
                "A"
            }
        );
    }
}