Ruby programming language | Computer Science homework help

I need someone really good with RUBY programming,, i have the whole code is written and i just need to make some changes ..

instead of puts(“Student Database”)
  puts(“——————————“)
  puts(“1 = Add new record to database”)
  puts(“2 = Edit existing record in database”)
  puts(“3 = Remove existing record from database”)
  puts(“4 = Display record(s) in database”)
  puts(“5 = Quit”)

so the user in this program choose numbers but i want to change them to letter such as a for add, e for edit, r  for remove as it’s showing below

I want it puts(“Student Database”)
  puts(“——————————“)
  puts(“a = Add new record to database”)
  puts(“e = Edit existing record in database”)
  puts(“r = Remove existing record from database”)
  puts(“d = Display record(s) in database”)
  puts(“q = Quit”)