static void Main(){
		
		long x=1221542567L;
		
		string result="Какое-то число не найдено";
		
		string y=Convert.ToString(x);
			
		char number_one='5';
		char number_two='4';
		
		int? number_one_place=null,number_two_place=null;
		
		for(int i=0;i<y.Length-1;i++)
			if(y[i]==number_one)
				number_one_place=i;
			else
				if(y[i]==number_two)
					number_two_place=i;
				
		if(number_one_place!=null && number_two_place!=null)
			if(number_one_place<number_two_place)
				result="Второе число дальше";
			else
				result="Первое число дальше";
			
		Console.WriteLine("number_one= "+number_one_place+" number_two="+number_two_place+". "+result);
		Console.ReadLine();
		
}