diff options
Diffstat (limited to '7.scm')
| -rwxr-xr-x | 7.scm | 52 |
1 files changed, 52 insertions, 0 deletions
@@ -0,0 +1,52 @@ +#!/usr/bin/env -S guile -s +!# +(use-modules (ice-9 regex) + (ice-9 textual-ports) + (srfi srfi-1)) + +(define (read-lines port) + (letrec ((loop (lambda (l ls) + (if (eof-object? l) + ls + (loop (get-line port) (cons l ls)))))) + (reverse (loop (get-line port) '())))) + +(define (hand-class hand) + (let ((hand-uniq (length (delete-duplicates (string->list hand))))) + (cond ((= 1 hand-uniq) 6) + ((= 2 hand-uniq) + (let ((x (string-length (string-filter (string-ref hand 0) hand)))) + (if (or (= 1 x) (= 4 x)) 5 4))) + ((= 3 hand-uniq) + (if (or (= 3 (string-length (string-filter (string-ref hand 0) hand))) + (= 3 (string-length (string-filter (string-ref hand 1) hand))) + (= 3 (string-length (string-filter (string-ref hand 2) hand)))) 3 2)) + ((= 4 hand-uniq) 1) + (else 0)))) + +(define (card-power card) + (length (member card '(#\A #\K #\Q #\J #\T #\9 #\8 #\7 #\6 #\5 #\4 #\3 #\2)))) + +(define (card-power-less lhs rhs) + (let ((i 0)) + (while (equal? (string-ref lhs i) + (string-ref rhs i)) + (set! i (1+ i))) + (< (card-power (string-ref lhs i)) (card-power (string-ref rhs i))))) + +(define (hand-less-than lhs rhs) + (let ((lhs-class (hand-class (car lhs))) + (rhs-class (hand-class (car rhs)))) + (if (equal? lhs-class rhs-class) + (card-power-less (car lhs) (car rhs)) + (< lhs-class rhs-class)))) + +(let* ((port (open-input-file "7.txt")) + (lines (read-lines port)) + (bids (sort (map (lambda (line) (let ((bid (string-split line char-set:whitespace))) + `(,(car bid) . ,(string->number (cadr bid))))) lines) hand-less-than)) + (winnings 0)) + (close-port port) + (do ((i 0 (1+ i))) ((= i (length bids))) + (list-set! bids i (* (+ i 1) (cdr (list-ref bids i))))) + (display (fold + 0 bids))) |