using System.Collections.Generic;
public static void Main()
int[] n = [1, 9, 9, 9, 1];
Console.WriteLine(GcdOfStrings("TAUXXTAUXXTAUXXTAUXXTAUXX","TAUXXTAUXXTAUXXTAUXXTAUXXTAUXXTAUXXTAUXXTAUXX"));
public static string GcdOfStrings(string str1, string str2) {
if(str1.Length < str2.Length){
if(str1.Substring(0,str2.Length) == str2){
str1 = str1.Substring(str2.Length);
if(str1.Substring(str2.Length).Length < str2.Length){