結果

問題 No.274 The Wall
ユーザー sansaqua
提出日時 2019-09-18 02:09:10
言語 Common Lisp
(sbcl 2.5.0)
結果
AC  
実行時間 804 ms / 2,000 ms
コード長 5,781 bytes
コンパイル時間 267 ms
コンパイル使用メモリ 50,644 KB
実行使用メモリ 291,096 KB
最終ジャッジ日時 2025-03-17 19:03:10
合計ジャッジ時間 3,230 ms
ジャッジサーバーID
（参考情報） 		judge5 / judge1
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ファイルパターン 結果
sample AC * 4
other AC * 23
権限があれば一括ダウンロードができます
コンパイルメッセージ
; compiling file "/home/judge/data/code/Main.lisp" (written 17 MAR 2025 07:03:06 PM):

; wrote /home/judge/data/code/Main.fasl
; compilation finished in 0:00:00.040

ソースコード

diff # 

;; -*- coding: utf-8 -*-
(eval-when (:compile-toplevel :load-toplevel :execute)
  (sb-int:defconstant-eqx OPT
    #+swank '(optimize (speed 3) (safety 2))
    #-swank '(optimize (speed 3) (safety 0) (debug 0))
    #'equal)
  #+swank (ql:quickload '(:cl-debug-print :fiveam) :silent t)
  #-swank (set-dispatch-macro-character
           #\# #\> (lambda (s c p) (declare (ignore c p)) (read s nil nil t))))
#+swank (cl-syntax:use-syntax cl-debug-print:debug-print-syntax)
#-swank (disable-debugger) ; for CS Academy

;; BEGIN_INSERTED_CONTENTS
(defmacro define-int-types (&rest bits)
  `(progn
     ,@(mapcar (lambda (b) `(deftype ,(intern (format nil "UINT~A" b)) () '(unsigned-byte ,b))) bits)
     ,@(mapcar (lambda (b) `(deftype ,(intern (format nil "INT~A" b)) () '(signed-byte ,b))) bits)))
(define-int-types 2 4 7 8 15 16 31 32 62 63 64)

(declaim (ftype (function * (values fixnum &optional)) read-fixnum))
(defun read-fixnum (&optional (in *standard-input*))
  (declare #.OPT
           #-swank (sb-kernel:ansi-stream in))
  (macrolet ((%read-byte ()
               `(the (unsigned-byte 8)
                     #+swank (char-code (read-char in nil #\Nul))
                     #-swank (sb-impl::ansi-stream-read-byte in nil #.(char-code #\Nul) nil))))
    (let* ((minus nil)
           (result (loop (let ((byte (%read-byte)))
                           (cond ((<= 48 byte 57)
                                  (return (- byte 48)))
                                 ((zerop byte) ; #\Nul
                                  (error "Read EOF or #\Nul."))
                                 ((= byte #.(char-code #\-))
                                  (setf minus t)))))))
      (declare ((integer 0 #.most-positive-fixnum) result))
      (loop
        (let* ((byte (%read-byte)))
          (if (<= 48 byte 57)
              (setq result (+ (- byte 48)
                              (* 10 (the (integer 0 #.(floor most-positive-fixnum 10)) result))))
              (return (if minus (- result) result))))))))

;;;
;;; Strongly connected components of directed graph
;;;

(defun make-scc (graph)
  "GRAPH := vector of adjacency lists"
  (declare #.OPT
           ((simple-array list (*)) graph))
  (let* ((n (length graph))
         (ords (make-array n :element-type 'uint31 :initial-element 0))
         (lows (make-array n :element-type 'uint31 :initial-element 0))
         (components (make-array n :element-type 'uint31))
         (stack (make-array n :element-type 'uint31))
         (in-stack (make-array n :element-type 'bit :initial-element 0))
         (time 0)
         (ord 0)
         (pointer 0))
    (declare (uint31 time ord pointer))
    (labels ((visit (v)
               (incf time)
               (setf (aref lows v) time
                     (aref ords v) time)
               (setf (aref stack pointer) v)
               (incf pointer)
               (setf (aref in-stack v) 1)
               (dolist (neighbor (aref graph v))
                 (cond ((zerop (aref ords neighbor))
                        (visit neighbor)
                        (setf (aref lows v)
                              (min (aref lows v) (aref lows neighbor))))
                       ((= 1 (aref in-stack neighbor))
                        (setf (aref lows v)
                              (min (aref lows v) (aref ords neighbor))))))
               (when (= (aref lows v) (aref ords v))
                 (loop
                   (decf pointer)
                   (let ((w (aref stack pointer)))
                     (setf (aref in-stack w) 0)
                     (setf (aref components w) ord)
                     (when (= v w)
                       (return))))
                 (incf ord))))
      (dotimes (v n)
        (when (zerop (aref ords v))
          (visit v)))
      components)))

(defmacro dbg (&rest forms)
  #+swank
  (if (= (length forms) 1)
      `(format *error-output* "~A => ~A~%" ',(car forms) ,(car forms))
      `(format *error-output* "~A => ~A~%" ',forms `(,,@forms)))
  #-swank (declare (ignore forms)))

;;;
;;; Body
;;;

(defun main ()
  (declare #.OPT)
  (let* ((n (read))
         (m (read))
         (ls (make-array (* 2 n) :element-type 'uint16))
         (rs (make-array (* 2 n) :element-type 'uint16))
         (graph (make-array (* 4 n) :element-type 'list :initial-element nil))
         (2n (* 2 n))
         (4n (* 4 n)))
    (declare (uint16 n m))
    (dotimes (i n)
      (let* ((l (read-fixnum))
             (r (read-fixnum)))
        (declare (uint16 l r))
        (setf (aref ls i) l
              (aref rs i) r
              (aref ls (+ i n)) (- m r 1)
              (aref rs (+ i n)) (- m l 1))))
    (labels ((negate (x)
               (declare (uint16 x))
               (let ((res (+ x 2n)))
                 (if (>= res 4n)
                     (- res 4n)
                     res)))
             (add-clause! (literal1 literal2)
               (declare (uint16 literal1 literal2))
               (push (negate literal2) (aref graph literal1))
               (push (negate literal1) (aref graph literal2))))
      (declare (inline negate))
      (dotimes (x 2n)
        (loop for y from (+ x 1) below 2n
              do (when (and (/= (+ x n) y)
                            (not (or (< (aref rs x) (aref ls y))
                                     (< (aref rs y) (aref ls x)))))
                   (add-clause! x y))))
      (dotimes (x n)
        (add-clause! (negate x) (negate (+ x n)))
        (add-clause! x (+ x n)))
      (let* ((comps (make-scc graph)))
        (declare ((simple-array uint31 (*)) comps))
        (write-line
         (if (loop for x below 2n
                   thereis (= (aref comps x)
                              (aref comps (+ x 2n))))
             "NO"
             "YES"))))))

#-swank (main)
0