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 C# (.NET Core 3.1.201) (judge verdict: Accepted)

using System;
using static System.Console;
using static System.Math;
using System.Collections.Generic;


namespace AtCoder
{
    public class Program
    {
        public static void Main(string[] args)
        {
            var s = ReadLine().Split(' ');
            var ans = 'a';
            string a = s[0];
            if (Char.IsUpper(a, 0))
            { ans = 'A'; }

            WriteLine(ans);
            Out.Flush();
        }

    }

    public static class MyMath
    {
        public static long Factorical(long n)
        { return n <= 1 ? 1L : n * Factorical(n - 1); }
        public static long Permutation(long n, long m)
        { return m == 0 ? 1L : (m == n) ? Permutation(n, m - 1) : n * Permutation(n - 1, m - 1); }
        public static long Combination(long n, long m)
        { return n - m > m ? Permutation(n, m) / Factorical(m) : Permutation(n, n - m) / Factorical(n - m); }
        public static long Gcd(long n, long m)
        { return n % m == 0 ? m : Gcd(m, n % m); }
        public static long Lcm(long n, long m)
        { return n * m / Gcd(n, m); }
        public static long Pow(long n, long m)
        { return (m == 1 || m == 0) ? 1L : n * Pow(n, m - 1); }
    }
}