Question 151
For each positive integer $n$, define the function $f_{n}(x) = |n - x|$. How many real solutions are there to
$$
\left(f_{1} \circ f_{2} \circ \cdots \circ f_{24} \circ f_{25}\right)(x) = 0?
$$
$$
\left(f_{1} \circ f_{2} \circ \cdots \circ f_{24} \circ f_{25}\right)(x) = 0?
$$