Storing array data into plain text and back

Hey Guys iv Created a simple hotel code that shows that you are able to input 10 customers in to room. it has a menu that:

("|V| To view all of the rooms.")
("|D| To delete a customer from a room.")
("|A| To add a customer to a room.")
("|E| To display empty rooms.")
("|F| To search for someone that occupies a room. (Please enter a letter to leave the menu)")

Here is my code if you want to check it out: http://ift.tt/1CwyqhT

iv tried many ways but i failed, i cant implement a code that stores program array data into a plain text file, or load program data back from the file into array.

i am not asking you do the work for me

i just need some tips or methods to implement this.

Edit: i may be asking for too much, but right now i am trying to show the data is shown once the user inputs stuff into a data file i.e additional choice on menu that will "Load program data back from the file into the array", any guidance tips will be appreciated.