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.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace A
{
    class Program
    {
        public static void Main(string[] args)
        {
            var s = ReadLine();

            var array = new string[] { "a", "i", "u", "e", "o" };

            Console.WriteLine((Array.IndexOf(array, s) > -1) ? "vowel" : "consonant");
            ReadLine();
        }

        /// <summary>
        /// コンビネーション
        /// </summary>
        /// <param name="n"></param>
        /// <param name="m"></param>
        /// <returns></returns>
        static int nCm(int n, int m)
        {
            if (m == 0) return 1;
            if (n == 0) return 0;
            return n * nCm(n - 1, m - 1) / m;
        }

        /// <summary>
        /// stringを一文字ずつintにキャストして配列に変換します。
        /// </summary>
        /// <param name="str"></param>
        /// <returns></returns>
        public static int[] StringCharArrayIntArray(string str)
        {
            List<int> b = new List<int>();
            for (int i = 0; i < str.Length; i++) {
                b.Add( int.Parse(str[i].ToString()));
            }
            return b.ToArray();
        }

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

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

        public static string[] ReadLineStringSplit(char a = ' ')
        {
            return ReadLine().Split(a).ToArray();
        }

        public static int[] ReadLineIntSpilit(char a = ' ')
        {
            return ReadLine().Split(a).Select(x => int.Parse(x)).ToArray();
        }

        static string[] GetAplhaLowerArray() => new string[]{ "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z"};
        static string[] GetAplhaUpperArray() => new string[] { "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z" };
    }
}