(C++) Is there a way to have a program run in the background and then call it again to add additional input?

I've been trying to program my own little database program that takes some numbers and stores them for later use... but I have no idea how to have an application like that stay in the background or refer to it later when I need it. For example I would like to do something like this...

[i] = stuff I type
[o] = computer printout

[i] CONSOLE:myLittleProgram insert number1
[o]CONSOLE:"myLittleProgram:" number1 was stored sucessfully..."
[i] CONSOLE:myLittleProgram insert number2
[o]CONSOLE:"myLittleProgram:" number2 was stored sucessfully..."
[i] CONSOLE:myLittleProgram view
[o]CONSOLE:myLittleProgram ...
[o]CONSOLE:2 numbers currently stored:
[o]CONSOLE:===================
[o]CONSOLE:|| 1 | number 1
[o]CONSOLE:|| 2 | number 2
[o]CONSOLE:====================
[o]CONSOLE:_

..... x minutes later ....

[i] CONSOLE:myLittleProgram view
[o]CONSOLE:myLittleProgram ...
[o]CONSOLE:2 numbers currently stored:
[o]CONSOLE:===================
[o]CONSOLE:|| 1 | number 1
[o]CONSOLE:|| 2 | number 2
[o]CONSOLE:====================
[i]CONSOLE:myLittleProgram insert number 3
[o]CONSOLE:"myLittleProgram:" number3 was stored sucessfully..."
[i] CONSOLE:myLittleProgram view
[o]CONSOLE:myLittleProgram ...
[o]CONSOLE:3 numbers currently stored:
[o]CONSOLE:===================
[o]CONSOLE:|| 1 | number 1
[o]CONSOLE:|| 2 | number 2
[o]CONSOLE:|| 3 | number 3
[o]CONSOLE:====================
/////////////////////////////////////////////////////////

Any advice or a pointer to the right documentation / tutorial /discussion would be appreciated thank-you!

EDIT: Format... made it easier to read (sorry)