Problem:
Score : 100 points

Problem Statement

Given a lowercase English letter c, determine whether it is a vowel. Here, there are five vowels in the English alphabet: a, e, i, o and u.

Constraints

c is a lowercase English letter.

Input

The input is given from Standard Input in the following format:

c

Output

If c is a vowel, print vowel. Otherwise, print consonant.

Sample Input 1

a

Sample Output 1

vowel

Since a is a vowel, print vowel.

Sample Input 2

z

Sample Output 2

consonant

Sample Input 3

s

Sample Output 3

consonant

Solution in C# (.NET Core 3.1.201) (judge verdict: Wrong Answer)

using System;
using System.Collections.Generic;

namespace cswork {
    class Program {
        static void Main (string[] args) {
            string s = ReadStr();
            if(s.Equals("a") || s.Equals("b") || s.Equals("c") || s.Equals("d") || s.Equals("e")){
                Write("vowel");
            }else{
                Write("consonant");
            }
            Exit ();
        }

        public static void Write (string str) {
            Console.WriteLine (str);
        }

        public static void Write (int i) {
            Console.WriteLine (i);
        }

        public static void Write (double d) {
            Console.WriteLine (d);
        }

        public static string ReadStr () {
            return Console.ReadLine ();
        }

        public static int ReadInt () {
            return int.Parse (Console.ReadLine ());
        }

        public static long Read () {
            return long.Parse (Console.ReadLine ());
        }

        public static double ReadDouble () {
            return double.Parse (Console.ReadLine ());
        }

        public static void Exit () { }

        public static List<string> ReadListStr () {
            return new List<string> (ReadStr ().Split (" "));
        }

        public static List<long> ReadList () {
            return ReadListStr ().ConvertAll (x => long.Parse (x));
        }

        public static List<int> ReadListInt () {
            return ReadListStr ().ConvertAll (x => int.Parse (x));
        }
    }
}