Write a recursive function named zigzag that returns a string of n characters as follows. The middle character $($or the middle two characters if $n$ is even$)$ is an asterisk $(*).$ All characters before the asterisks are ${?}^{\text{'}}>.$ All characters after are $>\text{'}.$ Report an error if $n$ is not positive. Ask for the user input to test the code.

Example: $n=6,$ pattern is if $n=5$ pattern is