int strip_q_marks(char *string_ptr){
        int n = strlen(string_ptr);
        int count = 0;
        for (int i = n; i > 0; i--){
                if (string_ptr[i] == '?'){
                        string_ptr[i] = '\0';
                        count = count + 1;
                } else {
                        break;
                }
        }
        return count;
}
Complete this program by writing the function strip_q_marks that takes
    a single string and returns an integer.

    The function should modify the string to remove any trailing question marks
    and return the number of question marks that were removed.

    Note that you should put the command-line argument in double quotes when you
    type it in. This prevents the shell from interpreting characters such as "?"
    or a space as special characters, and passes them to the program as is.

