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Problem 8: Largest product in a series

Link to the problem: https://projecteuler.net/problem=8.

Problem 8

The four adjacent digits in the 1000-digit number that have the greatest product are \(9 × 9 × 8 × 9 = 5832\).

73167176531330624919225119674426574742355349194934
96983520312774506326239578318016984801869478851843
85861560789112949495459501737958331952853208805511
12540698747158523863050715693290963295227443043557
66896648950445244523161731856403098711121722383113
62229893423380308135336276614282806444486645238749
30358907296290491560440772390713810515859307960866
70172427121883998797908792274921901699720888093776
65727333001053367881220235421809751254540594752243
52584907711670556013604839586446706324415722155397
53697817977846174064955149290862569321978468622482
83972241375657056057490261407972968652414535100474
82166370484403199890008895243450658541227588666881
16427171479924442928230863465674813919123162824586
17866458359124566529476545682848912883142607690042
24219022671055626321111109370544217506941658960408
07198403850962455444362981230987879927244284909188
84580156166097919133875499200524063689912560717606
05886116467109405077541002256983155200055935729725
71636269561882670428252483600823257530420752963450

Find the thirteen adjacent digits in the 1000-digit number that have the greatest product. What is the value of this product?

A simple solution

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(defwire main-wire
  ["73167176531330624919225119674426574742355349194934"
   "96983520312774506326239578318016984801869478851843"
   "85861560789112949495459501737958331952853208805511"
   "12540698747158523863050715693290963295227443043557"
   "66896648950445244523161731856403098711121722383113"
   "62229893423380308135336276614282806444486645238749"
   "30358907296290491560440772390713810515859307960866"
   "70172427121883998797908792274921901699720888093776"
   "65727333001053367881220235421809751254540594752243"
   "52584907711670556013604839586446706324415722155397"
   "53697817977846174064955149290862569321978468622482"
   "83972241375657056057490261407972968652414535100474"
   "82166370484403199890008895243450658541227588666881"
   "16427171479924442928230863465674813919123162824586"
   "17866458359124566529476545682848912883142607690042"
   "24219022671055626321111109370544217506941658960408"
   "07198403850962455444362981230987879927244284909188"
   "84580156166097919133875499200524063689912560717606"
   "05886116467109405077541002256983155200055935729725"
   "71636269561882670428252483600823257530420752963450"]
  (String.Join) = .inputStr

  0 >= .i >= .j >= .k >= .l
  1 >= .prod >= .max_prod
  "" >= .current

  (Repeat
   (-> .i (Math.Add 12) > .j
       1 > .prod
       (ForRange
        .i .j
        (-> > .k (Math.Add 1) > .l
            .inputStr (Slice .k .l) (ParseInt) (Math.Multiply .prod) > .prod))
       .prod (Max .max_prod) > .max_prod
       (Math.Inc .i))
   :Forever true
   :Until (-> .i (IsMore (- 1000 13))))

  .max_prod (Assert.Is 23514624000 true)
  (Log "Answer"))

(defmesh root)
(schedule root main-wire)
(run root)

[info] [2023-02-24 14:01:42.306] [T-5176] [logging.cpp::62] [main-wire] Answer: 23514624000