#!/usr/bin/guile -s
!#

(use-modules (ice-9 rdelim))

(define (read-lines)
  (let loop ((line (read-line)))
    (if
      (eof-object? line)
      '()
      (cons line (loop (read-line))))))

(define (map list mapper)
  (if
    (null? list)
    '()
    (cons (mapper (car list)) (map (cdr list) mapper))))

(define (first-last-combine current rest)
  (if
    (null? current)
    rest
    (if
      (null? rest)
      current
      (cons (car current) (cdr rest)))))

(define (first-last list predicate)
  (if
    (null? list)
    '()
    (first-last-combine
      (if
        (predicate (car list))
        (cons (car list) (cons (car list) '()))
        '())
      (first-last (cdr list) predicate))))

(define (sum numbers)
  (if
    (null? numbers)
      0
      (+ (car numbers) (sum (cdr numbers)))
      ))

(define (solve-line line)
  (
    #!(lambda (first-last-result) (sum (map first-last-result (lambda (char) (string->number (string char))))))!#
    (lambda (first-last-result) (string->number (list->string first-last-result)))
    (first-last
      (string->list line)
      (lambda (char) (if (char-numeric? char) #t #f)))))

(define (solve-all lines)
  (if
    (null? lines)
    0
    (+ (solve-line (car lines)) (solve-all (cdr lines)))
    ))

(display (solve-all (read-lines)))