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4. User (Search Train): After the authentification, the user can make search for a train and make a reservation. First of all the following GUI will appear to the user: - The user should enter two different stations: departure and arrival; also he should define the number of passengers; - If the inputs are empty of the stations are equals the system will show the following message: - When the user press the button "search" the system will open the file and try to find a train with the same defined departure and arrival stations and with a "max Passengers" greater than the "number of passenger" requested by the user. - You should check if the user input exists in the File. If the search is failed the System will show the following message: - If a train is found, the system will show a new GUI for the reservation