I believe the meaning of one beings life is directly proportional to the Effect they have had on the world. So in theory the meaning of ones life could be determined my a number and one persons life can be more meaningful than anothers if they have had a greater effect on the world.
The meaning of life is only commensurate to the intelligence which expounds it since there is no other meaning. Animals simply exist but the question does not. Proceed from there and intelligence becomes it’s syncopation!
According to your little signature equation, if you rearrange it slightly:
Bad effect + meaning = Good effect.
Is that intentional? 
Effect is definately a part of the concept of meaning, along with importance, intention, and what something stands for or symbolises.
What you intend the outcome of your life to be, what you do with it, how important it is, what it represents are what determines the meaning of your life.
But these things are all so subjective and could be anything according to what you compare it to, and so the idea of a specific meaning is a little absurd, even on a subjective level. And whether or not it is good or bad is equally arbitrary and absurd.
As has been said lots of times, meaning is what you make of it according to your values - compare & judge it with whatever you like - there is no objective meaning that is either good or bad unless you believe God.
The meaning of life is entirely subjective and infinitely more complex than the equation in your signature.
Wouldn’t some of those effects be ‘affects’?
the meaning of life changes from moment to moment, it’s whatever you pretend it is, what you say it is, and you’re as right as you want to be, as right as you let yourself be. i like monad’s answer better.
42
Odd, I’ve read the exact same anwser to this question on another forum. Maybe 42 really is the meaning of life .
Incomprehensible
There is a very popular book out where mice from space build a super computer that takes millions of years to compute the meaning of life. The answer lies in 1 humans brain lalalal… and the computer eventually says the answer is 42.