Kumite

namespace Solution {
  using NUnit.Framework;
  using System;

  [TestFixture]
  public class SolutionTest
  {
    [Test]
    public void TrueTests()
    {
      Assert.AreEqual(1, Kata.SameCase('a', 'u'));
      Assert.AreEqual(1, Kata.SameCase('A', 'U'));
      Assert.AreEqual(1, Kata.SameCase('Q', 'P'));
      Assert.AreEqual(1, Kata.SameCase('w', 'y'));
      Assert.AreEqual(1, Kata.SameCase('c', 'm'));
      Assert.AreEqual(1, Kata.SameCase('N', 'W'));
    }
    [Test]
    public void FalseTests()
    {
      Assert.AreEqual(0, Kata.SameCase('a', 'U'));
      Assert.AreEqual(0, Kata.SameCase('A', 'u'));
      Assert.AreEqual(0, Kata.SameCase('Q', 'p'));
      Assert.AreEqual(0, Kata.SameCase('w', 'Y'));
      Assert.AreEqual(0, Kata.SameCase('c', 'M'));
      Assert.AreEqual(0, Kata.SameCase('N', 'w'));
    }
    [Test]
    public void NotLetters()
    {
      Assert.AreEqual(-1, Kata.SameCase('a', '*'));
      Assert.AreEqual(-1, Kata.SameCase('A', '%'));
      Assert.AreEqual(-1, Kata.SameCase('Q', '1'));
      Assert.AreEqual(-1, Kata.SameCase('w', '-'));
      Assert.AreEqual(-1, Kata.SameCase('c', '8'));
      Assert.AreEqual(-1, Kata.SameCase('N', ':'));
    }
    [Test]
    public void RandomTest() {
      string chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmopqrstuvwxyz1234567890~/*-+:.,><.#@!&";
      Random rand = new Random();
      char char1 = 'a';
      char char2 = 'a';
      
      for (int i = 0; i < 200; i++) {
        char1 = chars[rand.Next(0,76)];
        char2 = chars[rand.Next(0,76)];
        Assert.AreEqual(SameCaseSolution(char1,char2), Kata.SameCase(char1, char2));
      }
    }
    
    private static int SameCaseSolution(char a, char b) {
      if (!char.IsLetter(a) || !char.IsLetter(b)) return -1;
      if ((a >= 97) == (b >= 97)) return 1;
      return 0;
    }
  }
}