Reverse a string using recursion.

reverse_string_with_recursion.cpp

string reverse(string s) {
    int length = s.size();
    if (length <= 1) { 
        return s;
    }
   
    string middle_part = string(s.begin()+1, s.end()-1);
    string reversed_middle_part = reverse(middle_part);
    
    string first_char = string(s.begin(), s.begin()+1);
    string last_char = string(s.end()-1, s.end());
    string reversed =  last_char + reversed_middle_part + first_char;
    return reversed;
}