(0) write a function called displaymenu that does not take any parameters, but returns an integer representing your user's menu choice. your program's main function should only comprise of the following: a do/while loop with the displaymenu function call inside the loop body switch/case, or if/else if/ for handling the calls of the functions based on the menu choice selected in displaymenu. the do/while loop should always continue as long as the user does not choose to quit the program.