'x' and 'y'

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Well, I have in my posession 'x' and frankly 'x' is enough to keep most beings happy.
But I somehow manage to scent a 'y'. And irrespective of whether 'y' is positive or negative, I end up fiddling with 'y' to have 'x+y'...
Call it my comedy or tragedy or whatever you may like... I need to find the 'y's at regular intervals.