You can use stl if needed

7. (Data processing) a. You have collected information about cities in your state. You decide to store each city's name, population, and mayor in a file. Write a C++ program to accept data for a number of cities from the keyboard and store the data in a file in the order in which it's entered. b. Read the file created in Exercise 7a, sort the data alphabetically by city name, and display the data