#lang racket

(with-input-from-file "../input/01"
  (lambda ()
    (for/fold ([cnt 0]
               [last null]
               #:result cnt)
              ([line (in-lines)])
      (let ([num (string->number line)])
        (values (cond [(null? last) cnt]
                      [(> num last) (+ cnt 1)]
                      [else cnt])
                num)))))