Going from pseudocode to scheme -


key <-5381 each character c in w key <-33.key + ctv(c) end for

this pseudocode key function implemented in scheme life of me cant figure out how translate actual code. appreciated. , ctv function converts each character integer value ie 1 , z 26

i'll give general structure of solution, because looks homework , should try solve yourself:

(define (key str)   (let loop ((chars <???>) ; transform string list of chars              (acc 5381))   ; initial value of accumulator     (if <???>              ; if list of chars empty         acc                ; return accumulator         (loop <???>        ; otherwise advance recursion on list               <???>))))    ; update accumulator, use `ctv` , apply formula

notice we're using recursion implement looping, traverse on parameter chars (the list of characters) , use parameter acc accumulating result returned @ end. instance, here's how value of acc variable gets updated on successive iterations:

acc: 5381              ; initial  value,  acc = 5381 acc: 33 * acc + ctv(d) ; processing 'd',  acc = 177577 acc: 33 * acc + ctv(a) ; processing 'a',  acc = 5860042 acc: 33 * acc + ctv(y) ; processing 'y',  acc = 193381411

finally, don't forget test it, this:

(key "day") => 193381411

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