Help with optimisation

        public (int length, string LongestString) MyLongestStringValueTuple(string[] strings){
        if(strings.Length == 0){
            return (-1, string.Empty);
        }
        string longest = strings[0];
        foreach(string str in strings){
            if(str.Length > longest.Length){
                if(str.Length == longest.Length){
                    continue;
                }
                longest = str;
            }
        }
        return (longest.Length, longest);