C++ :: Possible To Store A New Line At The Above Of Text File

I need to store the last 3 deposit that I have in my deposit. I have few option but i dont which would be easy

1.Store all deposit to the text file (store always in a new line), and display the last three deposit from the text file.

dep 1 - 60
dep 2 - 40
dep 3 - 100 print 100
dep 4 - 50 print 50
dep 5 - 50 print 50

2. I think this option is more difficult, when it reach deposit 4, to get rid deposit 1

So when i make a deposit 4, the deposit 1 get's ride
dep 2 - 50
dep 3 - 100
dep 4 - 70

Right now i can only display one deposit (last one), then i close the program and run again and i make another deposit it overwrites a new deposit.

My code.
To show sure my deposit that has been made.
double depSave () {
int option;
float dep1,dep2,dep3;// Declare your variables
dep1 = dep2 = dep3 = 0; // Set them all to 0

system ("cls");
string path = "deposit.txt"; // Storing your filename in a string

[Code] ....

Where is says "save deposit" in comment that where it saves to the deposit text file, that going to be output to the depSave function.