using System;
using System.Text.RegularExpressions;
public class Test
{
public static void Main()
{
var rx = new Regex("^1+");
var s = "11111aA$xx1111xxdj$%%";
var res = rx.Replace(s, "");
Console.WriteLine(res);
}
}
dXNpbmcgU3lzdGVtOwp1c2luZyBTeXN0ZW0uVGV4dC5SZWd1bGFyRXhwcmVzc2lvbnM7CgpwdWJsaWMgY2xhc3MgVGVzdAp7CglwdWJsaWMgc3RhdGljIHZvaWQgTWFpbigpCgl7CgkJdmFyIHJ4ID0gbmV3IFJlZ2V4KCJeMSsiKTsKCQl2YXIgcyA9ICIxMTExMWFBJHh4MTExMXh4ZGokJSUiOwogICAgICAgICAgICAgICAgdmFyIHJlcyA9IHJ4LlJlcGxhY2UocywgIiIpOwoJCUNvbnNvbGUuV3JpdGVMaW5lKHJlcyk7Cgl9Cn0=