Why would you want to use something like “ඞ” when there’s 26 letters in the alphabet, which can each be written in upper or lower case, and can have hats, underscores, overbars, primes, double-primes, indices, etc., to make them distinct from each other if you run out. You can also use lower and upper case Greek letters. What would be the motivation for using ඞ? The graders might appreciate if you take the assignment seriously and adhere to standard mathematical conventions (which are to use English and Greek letters, for the most part).