Tony Gladdis; Starting out With Java $4$th Edition $-$ Chapter $15$ Programming Challenge A $$ Add$-$a$-$String $($Would like this coded and is able to complie and run without error, please$)$

Specifications:

Write a recursive program that accepts an alphanumeric String argument and returns the sum of each of it$$s characters. The alpha characters are equal to their placement in the ordered alphabet, e$.$g$.,$ A$=1,$ a$=1,$ C$=3,$ e$=5,$ etc.; and numerals are equal to their corresponding number, e$.$g$.,1=1.$

For example, the string $1$Bz$6$ would equal $35$ because $1+2+26+6=35$ The direct $($brutal$)$ approach to recursion would result in the calling sequence $$bottoming out$$ at N call levels deep. That is$,$ for a string of N characters, when the recursion starts to unwind, it would have called itself N times, and there would be $($N$-1)$hanging$$ method calls waiting for return values. This can get resource expensive. However, there are ways to reduce this depth, so that processing is never anywhere near N levels deep for non$-$trivial values of N$.$

Write your recursive code in such a way that processing never goes more than $70\%$ of N$.$ For example, for a string of $10$ characters, each of them is processed using recursion, but processing is never more than $6$ levels deep. $($This is not needed but would be greatly appreciated if added, thank you!$)$