to_string | Rust : make those primitives into strings

I have an application where I am receiving a string with some repetitive characters. I am receiving input as a String. How to remove the characters from specific index?

main.rs

Say I am building a record type:

My code won't compile and I don't know how to fix it. It looks like the problem is maybe with the "=" operator but I'm not sure. I'm trying to apply a given function on the elements of the sorted list in order to get a different sorted list, but it says that I'm using different arguments than the expected. My code looks like-

I am reading through the Rust book and doing the optinal exercise along the way. I've finished the chapter 8 (Common Collections) and am trying the last exercise. The exercise instructions are:

Using a hash map and vectors, create a text interface to allow a user to add employee names to a department in a company. For example, “Add Sally to Engineering” or “Add Amir to Sales.” Then let the user retrieve a list of all people in a department or all people in the company by department, sorted alphabetically.

What I want my program to do is firstly ask the user if they want to add a new employee, if no, the program ends else it allows them to continously add an employee until the user declines to add any more.

I've chosen to simply start with the initial user prompt asking if they want to add a new employee. I start with an empty String for the user input, once the user enters their response there is a while loop that repeats until the user enters a valid response ([Y/n]). Since the condition for the while loop is when the response is not equal to "y" or "n" I expected correct responses to skip the while loop but instead the while loop is always entered and never exited no matter what. Since I'm new to Rust I'm not sure if there some obvious or idiosyncratic reason for this behaviour. I'll also add that I remove whitespace (incl. \n) from the response and make the response lowercase in the while loop condition, all of which can be seen in my code below.

I'm trying to print a Sorted List and it looks like the list itself is correct- by printing the inner results, but when I try to print the whole list it shows some weird symbols and crashes. Where am I wrong? This is my main with the function I'm calling in "apply":

My dataframe df is:

I have a function that takes in a Vec value. I want to use this function on values contained inside my_ref, so I need to extract a Vec out of a Rc>>.

I thought I could do this by dereferencing a borrow of my my_ref, just like I would for a Rc>> or Rc>> value:

My dataframe df is:

I am trying to send a post request in C++ using socket programming, but the request doesnt seem to get executed. I am unsure of whether or not the syntax of the POST request is correct or not. Here is the request that I am sending