From 04a8190ccb02b1606cdae1e4436f5d2429965f81 Mon Sep 17 00:00:00 2001 From: Lowl3v3l Date: Tue, 9 May 2017 20:57:45 +0200 Subject: [PATCH] racket solutions for problems 6 7 and 8 --- 6/euler6.rkt | 4 ++++ 7/euler7.rkt | 12 ++++++++++++ 8/euler8.rkt | 41 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 57 insertions(+) create mode 100644 6/euler6.rkt create mode 100644 7/euler7.rkt create mode 100644 8/euler8.rkt diff --git a/6/euler6.rkt b/6/euler6.rkt new file mode 100644 index 0000000..abcaa30 --- /dev/null +++ b/6/euler6.rkt @@ -0,0 +1,4 @@ +#lang racket + +(- (* (apply + (range 1 101)) (apply + (range 1 101))) + (foldl + 0 (map (λ (x) (* x x)) (range 1 101)))) \ No newline at end of file diff --git a/7/euler7.rkt b/7/euler7.rkt new file mode 100644 index 0000000..e62314b --- /dev/null +++ b/7/euler7.rkt @@ -0,0 +1,12 @@ +#lang racket + +(require math/number-theory) + +(define (nth-prime it n primes) + (if (equal? n (length primes)) + (car primes) + (if (prime? it) + (nth-prime (+ it 2) n (cons it primes)) + (nth-prime (+ it 2) n primes)))) + +(nth-prime 3 10001 (list 2)) \ No newline at end of file diff --git a/8/euler8.rkt b/8/euler8.rkt new file mode 100644 index 0000000..b1907e8 --- /dev/null +++ b/8/euler8.rkt @@ -0,0 +1,41 @@ +#lang racket + +(define num + (map (λ (x) (- (char->integer x) 48)) + (string->list + (string-replace +"73167176531330624919225119674426574742355349194934 +96983520312774506326239578318016984801869478851843 +85861560789112949495459501737958331952853208805511 +12540698747158523863050715693290963295227443043557 +66896648950445244523161731856403098711121722383113 +62229893423380308135336276614282806444486645238749 +30358907296290491560440772390713810515859307960866 +70172427121883998797908792274921901699720888093776 +65727333001053367881220235421809751254540594752243 +52584907711670556013604839586446706324415722155397 +53697817977846174064955149290862569321978468622482 +83972241375657056057490261407972968652414535100474 +82166370484403199890008895243450658541227588666881 +16427171479924442928230863465674813919123162824586 +17866458359124566529476545682848912883142607690042 +24219022671055626321111109370544217506941658960408 +07198403850962455444362981230987879927244284909188 +84580156166097919133875499200524063689912560717606 +05886116467109405077541002256983155200055935729725 +71636269561882670428252483600823257530420752963450" "\n" "")))) + +(define pivot 0) + +(define (find-max-product n) + (if (< (length n) 13) + pivot + (if (> (apply * (take n 13)) pivot) + (begin + (set! pivot (apply * (take n 13))) + (find-max-product (cdr n))) + (find-max-product (cdr n))))) + +(find-max-product num) + + \ No newline at end of file