• Re: project euler problems in forth

    From B. Pym@Nobody447095@here-nor-there.org to comp.lang.lisp on Mon Sep 1 13:52:37 2025
    From Newsgroup: comp.lang.lisp

    Using names.txt (right click and 'Save Link/Target As...'), a 46K
    text file containing over five-thousand first names, begin by
    sorting it into alphabetical order. Then working out the
    alphabetical value for each name, multiply this value by its
    alphabetical position in the list to obtain a name score.

    For example, when the list is sorted into alphabetical order, COLIN, which is worth 3 + 15 + 12 + 9 + 14 = 53, is the 938th name in the
    list. So, COLIN would obtain a score of 938 * 53 = 49714.

    What is the total of all the name scores in the file?

    Gauche Scheme

    (use srfi-13) ;; string-tokenize
    (use srfi-14) ;; character sets
    (use srfi-42) ;; sum-ec
    (use file.util) ;; file->string

    (define (name-score name i)
    (* i (sum-ec (:string chr name) (- (char->integer chr) 64))))

    (let1 names
    (sort (string-tokenize
    (file->string "names.txt") char-set:upper-case))
    (sum-ec
    (:list name (index i) names)
    (name-score name (+ i 1))))

    ===>
    871198282


    --- Synchronet 3.21a-Linux NewsLink 1.2
  • From B. Pym@Nobody447095@here-nor-there.org to comp.lang.lisp on Mon Sep 1 18:59:39 2025
    From Newsgroup: comp.lang.lisp

    B. Pym wrote:

    Using names.txt (right click and 'Save Link/Target As...'), a 46K
    text file containing over five-thousand first names, begin by
    sorting it into alphabetical order. Then working out the
    alphabetical value for each name, multiply this value by its alphabetical position in the list to obtain a name score.

    For example, when the list is sorted into alphabetical order, COLIN, which is worth 3 + 15 + 12 + 9 + 14 = 53, is the 938th name in the list. So, COLIN would obtain a score of 938 * 53 = 49714.

    What is the total of all the name scores in the file?

    Gauche Scheme

    (use srfi-13) ;; string-tokenize
    (use srfi-14) ;; character sets
    (use srfi-42) ;; sum-ec
    (use file.util) ;; file->string

    (define (name-score name i)
    (* i (sum-ec (:string chr name) (- (char->integer chr) 64))))

    (let1 names
    (sort (string-tokenize
    (file->string "names.txt") char-set:upper-case))
    (sum-ec
    (:list name (index i) names)
    (name-score name (+ i 1))))

    ===>
    871198282

    Without loading any libraries.

    (define (name-score name)
    (define (chrval c) (max 0 (- (char->integer c) 64)))
    (apply + (map chrval (string->list name))))

    (let1 names
    (sort
    (string-split
    (with-input-from-file "E:names.txt" (cut read-line))
    #\,))
    (fold + 0 (map * (map name-score names) (lrange 1))))

    ===>
    871198282

    --- Synchronet 3.21a-Linux NewsLink 1.2