Bounded variation implies Borel measurable

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Suppose that $f\colon[a, b] \to \mathbb{R}$ is a function of bounded variation. Show that $f$ is Borel measurable.

I was wondering if I could get a hint.

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You see that for $ f \in BV([a,b]) $ you can write $ f = g - h $ where $ g(x) = V^x_a(f) $ and $ h = g-f $ where both $g $ and $h$ are monotonically increasing hence have countably many discontinuities.