using System;
using System.IO;
using System.Text.RegularExpressions;
public class Test
{
public static void Main()
{
var str = " modif-i-ed a-im";
var res = Regex.Replace(str, @"-?\b([a-zA-Z])\b-", "y");
Console.WriteLine(res);
}
}
dXNpbmcgU3lzdGVtOwp1c2luZyBTeXN0ZW0uSU87CnVzaW5nIFN5c3RlbS5UZXh0LlJlZ3VsYXJFeHByZXNzaW9uczsKCnB1YmxpYyBjbGFzcyBUZXN0CnsKCXB1YmxpYyBzdGF0aWMgdm9pZCBNYWluKCkKCXsKCQl2YXIgc3RyID0gIiBtb2RpZi1pLWVkICBhLWltIjsKCQl2YXIgcmVzID0gUmVnZXguUmVwbGFjZShzdHIsIEAiLT9cYihbYS16QS1aXSlcYi0iLCAieSIpOwoJCUNvbnNvbGUuV3JpdGVMaW5lKHJlcyk7Cgl9Cn0=