When I write to my file it clears all the previous data in that file

Question

I've been scanning through stackoverflow but I'm not finding any previous posts on my situation.

My program I want to write is just something to keep track of daily tips, hours worked, and number of days worked. So far it prints and creates a tips.txt file, but for some reason every time I run the program to input additional numbers it clears the previous entries . Still a lot of work that needs to be done, but I want to fix this problem first. Any ideas?

#include <fstream>
#include <iostream>
using namespace std;
int daysWorked(int); // Caculates the number of days worked
int hoursWorked(int); // Caculates hours worked
double profit(double); // Caculates the profit year to date

int main()
{
double tip;
int hours;
int month, day;
ofstream readFile;

cout << " Enter the month and then the day,  followed by hours worked, followed by money made" << endl;

if (!"tips.txt") // checks to see if tips.txt exists
{
    ofstream readFile("tips.txt"); // if tips.txt doesn't exists creates a .txt
}
else
    readFile.open("tips.txt" , std::ios::app && std::ios::in && std::ios::out); // if tips.txt exits just opens it? 

if (cin >> month >> day >> hours >> tip) // reads in the user input
{
    cout << endl;
    readFile << " Date :" <<  month << "/" <<  day << " " <<  "Hours:" << hours << " " << "Money made: " << tip << endl; // prints out the user input 
    cout << endl;
    readFile.close();
}

return 0;

}

Answer 1

Remove the following code:

// As rpattiso stated, this does not test for the existence of a file
//if (!"tips.txt") // checks to see if tips.txt exists
//{
//    ofstream readFile("tips.txt"); // if tips.txt doesn't exists creates a .txt
//}
//else

This alone should be sufficient:

// This will create the file if it doesn't exist and open existing files for appending (so you don't need to test if the file exists)
ofstream readFile.open("tips.txt" , std::ios::app); // open for writing in append mode