$L^p$ spaces inclusion

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Show that for any measurable function $f$ in a measure space, we have: $$ ||f||_p \leq \max\{||f||_r ,||f||_s \} $$ whenever $0<r<p<s$. Now by splitting the integrals into parts where $f>1$ and $f\leq 1$, we could easily show that
$$ ||f||_p \leq ||f||_r+||f||_s \ $$ But I have no idea how to show the stronger inequality as above.