I can't print a vector inside a switch case - c++

Question

This is my first question here. I am just beginning to learn C++ and I am stuck at this exercise:
Your program should display a menu options to the user as follows:
P--Print the vector
A--Add a number
M--Display mean of the number
S--Display the smallest number
L--Display the largest number
Q--Quit
Enter your choice:
Basically, I need to do a menu for these operations. I got stuck at the part of printing the vector. I already tried to use (for auto:....) and also tried with the normal index (int i = 0...), but the contents in the vector don't appear, only the message "This is your list of numbers:". I also tried to create a function to make sure that the user was inputting an integer in the A case, but did not know how to do it :(
This is my code:
#include <iostream>
#include <vector>
using namespace std;
int main()
{
bool control_end = false;
do
{
cout << "Please enter your desired function within the menu: " << endl;
cout << endl;
cout << "P--Print list of numbers" << endl;
cout << "A--Add a number"<< endl;
cout << "M--Display mean of the number"<< endl;
cout << "S--Display the smallest number"<< endl;
cout << "L--Display the largest number"<< endl;
cout << "Q--Quit "<< endl;
cout << endl;
cout << "Enter your choice: ";
char letra{};
cin >> letra;
vector<int> vector{};
switch(letra)
{
case 'A':
case 'a':
{
cout << "Please enter the value (integer) to be added to vector: ";
int value_add;
cin >> value_add;
cout << endl;
vector.push_back(value_add);
//(later do it) create a function to ensure that the value is an integer
break;
}
case 'p':
case 'P':
{
cout << "This is your list of numbers: \n";
for (unsigned int i=0 ;i < vector.size(); i++)
cout << vector[i] << " ";
break;
}
case 'm':
case 'M':
cout << "test M";
break;
case 's':
case 'S':
cout << "test S";
break;
case 'L':
case 'l':
cout << "test L";
break;
case 'q':
case 'Q':
cout << "Thank you for using the program" << endl;
control_end = true;
break;
default:
cout << "Invalid char. " << endl;
cout << endl;
break;
}
for(auto vec: vector)
cout << vec << endl;
}
while (control_end !=true);
return 0;
}

Answer 1

You created the variable vector inside your loop, so at the end of the loop the variable get destroyed and a new empty one is created on the next iteration. So, if you want your variable to retain values between loop iterations, you should declare it outside of the loop scope, the same way you did with the variable control_end.