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# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Linq;
using System.Collections;
using System.Collections.Generic;

namespace NotFounds
{
    public class Program
    {
        public static void Main(string[] args)
        {
            new Program().Solve();
        }

        public void Solve()
        {
            var cin = new MyInputStream();
            var c = Console.Read();
            var vowels = new char[] { 'a', 'i', 'u', 'e', 'o' };
            Console.WriteLine(vowels.Where(i => i == c).Count()  != 0 ? "vowel" : "consonant");
        }
    }

    public class MyInputStream
    {
        private char separator = ' ';
        private Queue<string> inputStream;
        public MyInputStream(char separator = ' ')
        {
            this.separator = separator;
            inputStream = new Queue<string>();
        }

        public string Read()
        {
            if (inputStream.Count != 0) return inputStream.Dequeue();
            string[] tmp = Console.ReadLine().Split(separator);
            for (int i = 0; i < tmp.Length; i++)
            {
                inputStream.Enqueue(tmp[i]);
            }
            return inputStream.Dequeue();
        }
        public string ReadLine()   { return Console.ReadLine(); }
        public int    ReadInt()    { return int.Parse(Read()); }
        public long   ReadLong()   { return long.Parse(Read()); }
        public double ReadDouble() { return double.Parse(Read()); }
    }

    public class MyUtility
    {
        /// <summary>2値を入れ替える</summary>
        public static void Swap<T>(ref T m, ref T n)
        {
            T tmp = m;
            m = n;
            n = tmp;
        }

        public static void PutYN(bool f)
        {
        	Console.WriteLine(f ? "YES" : "NO");
        }
    }
}