lebesgue integral of S

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Let $S$ be a bounded measurable subset of $\mathbb R$. Let $f \colon S → (0,\infty)$ be Lebesgue integrable. Prove that

$$\lim_{n\to\infty}\int_S\ f^{1/n} \;\mathrm{d}m = m(S)$$

Where $m(S)$ is the Lebesgue measure of $S$.

There is a hint that let $S = A \cup B$, where $A = f^{−1}((0, 1))$ and $B = f^{−1}([1,+\infty))$.

And the sequence of functions $h_n\ (n = 1, 2, 3, \dots),$ where $h_n(x) = ({f(x)})^{1/n}$.

How can I apply monotone convergence theorem to the given hint.