【Question 11】  
Arrange the numbers $1 \sim 5$ in a row to form a five-digit number, such that each digit is not greater than the average of the two adjacent digits (excluding the ten-thousands and units place). The five-digit numbers that meet the requirement are $\qquad$.
【Analysis and Solution】
Obviously, 5 must be at the ends (i.e., 5 must be in the ten-thousands place or the units place);
and 4 must be at the ends or between 3 and 5;
(1) If 4 is at the ends (i.e., 4 is in the ten-thousands place or the units place);

Consider the form $\overline{4 \square \square 5}$, 3 cannot be in the middle (i.e., 3 cannot be in the hundreds place),
$43215, 41235, 42135$ meet the requirements;
By symmetry, 51234, 53214, 53124 also meet the requirements;
(2) If 4 is between 3 and 5;

Consider the form $\overline{543 \square \square}$, it can only be 54321;
By symmetry, 12345 also meets the requirements;
In summary, the five-digit numbers that meet the requirements are $43215, 41235, 42135, 51234, 53214, 53124, 54321, 12345$.