Physics chads: is it possible to define the Energy of a particle in a single equation?

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Let's be honest for a second. We all know the "right equation" in particular circumstances:

a) for anything massive and stationary: E = mc^2
b) for anything massive and moving: E = sqrt((pc)^2 + (mc^2)^2)
c) for anything massless and moving: E = hf [where 'f' represents frequency]
d) for anything massless and stationary: E = 0

So what is the general equation for the Energy of particle as a function of its mass and velocity?