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author | HJ <thechairman@thechairman.info> | 2021-12-09 18:05:04 -0500 |
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committer | HJ <thechairman@thechairman.info> | 2021-12-09 18:05:04 -0500 |
commit | 527bc4762f9c66c9244f0ac1fbee6357478ac9ef (patch) | |
tree | ecd3ffc97de5aab201699f93aab1e0417ac3d25d /2020 | |
download | gleam_aoc-527bc4762f9c66c9244f0ac1fbee6357478ac9ef.tar.gz gleam_aoc-527bc4762f9c66c9244f0ac1fbee6357478ac9ef.zip |
putting all my solutions together in 1 repository
Diffstat (limited to '2020')
-rw-r--r-- | 2020/day-01/day-01.rkt | 23 | ||||
-rw-r--r-- | 2020/day-02/day-02.rkt | 45 | ||||
-rw-r--r-- | 2020/day-03/day-03.rkt | 22 |
3 files changed, 90 insertions, 0 deletions
diff --git a/2020/day-01/day-01.rkt b/2020/day-01/day-01.rkt new file mode 100644 index 0000000..56c0b87 --- /dev/null +++ b/2020/day-01/day-01.rkt @@ -0,0 +1,23 @@ +#lang racket +(require "../../jj-aoc.rkt" + threading) + +(define entries + (~>> (open-day 01 2020) + (port->list read) + list->set)) + +;; part 1 +(define (look-for-complement xs) + (define x (set-first xs)) + (cond + [(set-member? xs (- 2020 x)) (* x (- 2020 x))] + [else (look-for-complement (set-rest xs))])) + +(time (look-for-complement entries)) + +;; part 2 +(time (for*/first ([x (in-set entries)] + [y (in-set (set-subtract entries (set x)))] + #:when (set-member? (set-subtract entries (set x y)) (- 2020 x y))) + (* x y (- 2020 x y))))
\ No newline at end of file diff --git a/2020/day-02/day-02.rkt b/2020/day-02/day-02.rkt new file mode 100644 index 0000000..3296d32 --- /dev/null +++ b/2020/day-02/day-02.rkt @@ -0,0 +1,45 @@ +#lang racket +(require "../../jj-aoc.rkt" + threading) + +(struct policy (least most char pwd) #:transparent) + +(define (make-policy least-str most-str char-str pwd) + (policy (string->number least-str) + (string->number most-str) + (string-ref char-str 0) + pwd)) + +(define policies + (for/list ([l (in-lines (open-day 02 2020))]) + (~>> l + (regexp-match #px"(\\d+)-(\\d+) (\\w): (.*)") + rest + (apply make-policy)))) + +;; part 1 +(define (valid-policy? p) + (~>> p + policy-pwd + string->list + (count (curry char=? (policy-char p))) + ((λ (n) (and (>= n (policy-least p)) + (<= n (policy-most p))))))) + +(for/sum ([p (in-list policies)] + #:when (valid-policy? p)) + 1) + +;; part 2 +(define (valid-revised-policy? p) + (~>> p + policy-pwd + string->list + ((λ (lst) (list (list-ref lst (sub1 (policy-most p))) + (list-ref lst (sub1 (policy-least p)))))) + (count (curry char=? (policy-char p))) + (= 1))) + +(for/sum ([p (in-list policies)] + #:when (valid-revised-policy? p)) + 1)
\ No newline at end of file diff --git a/2020/day-03/day-03.rkt b/2020/day-03/day-03.rkt new file mode 100644 index 0000000..f540ee6 --- /dev/null +++ b/2020/day-03/day-03.rkt @@ -0,0 +1,22 @@ +#lang racket +(require "../../jj-aoc.rkt" + threading) + +(define (check-for-trees run rise) + (for*/sum ([(row i) (in-indexed (port->lines (open-day 3 2020)))] + #:when (= 0 (modulo i rise)) + [possible-tree (in-value (sequence-ref (in-cycle row) (* (/ run rise) i)))] + #:when (and (char=? possible-tree #\#))) + 1)) + +;; part 1 +(check-for-trees 3 1) + +;; part 2 +(~>> '((1 1) + (3 1) + (5 1) + (7 1) + (1 2)) + (map (curry apply check-for-trees)) + (apply *))
\ No newline at end of file |