using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Text.RegularExpressions; using System.Threading.Tasks; namespace _02_WormIpsum { class WormIpsum { static void Main(string[] args) { var input = Console.ReadLine(); var pattern = (@"^([A-Z]{1})([^\.]*)\.$"); while (input != "Worm Ipsum") { if (!Regex.IsMatch(input, pattern)) { input = Console.ReadLine(); continue; } var inputArr = input.Split(new[] { ' ','.' }, StringSplitOptions.RemoveEmptyEntries).Select(x => x.Trim()).ToArray(); foreach (var word in inputArr) { var mostRepeatedLetter = word.GroupBy(x => x).OrderByDescending(x => x.Count()).First().Key; int ocurrences = word.Count(c => c == mostRepeatedLetter); if (ocurrences >= 2) { string wordToReplace = new string(mostRepeatedLetter, word.Length); var index = Array.FindIndex(inputArr, x => x == word); inputArr[index] = wordToReplace; } } Console.WriteLine(String.Join(" ",inputArr)+ "."); input = Console.ReadLine(); } } } }