結果
| 問題 |
No.972 選び方のスコア
|
| コンテスト | |
| ユーザー |
 sansaqua
|
| 提出日時 | 2020-01-17 23:27:31 |
| 言語 | Common Lisp (sbcl 2.5.0) |
| 結果 |
AC
|
| 実行時間 | 165 ms / 2,000 ms |
| コード長 | 7,366 bytes |
| コンパイル時間 | 1,147 ms |
| コンパイル使用メモリ | 58,444 KB |
| 実行使用メモリ | 35,600 KB |
| 最終ジャッジ日時 | 2024-06-26 01:06:17 |
| 合計ジャッジ時間 | 6,952 ms |
|
ジャッジサーバーID （参考情報） |
judge1 / judge5 |
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| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 32 |
コンパイルメッセージ
; compiling file "/home/judge/data/code/Main.lisp" (written 26 JUN 2024 01:06:10 AM): ; wrote /home/judge/data/code/Main.fasl ; compilation finished in 0:00:00.113
ソースコード
;; -*- 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
;; enclose the form with VALUES to avoid being captured by LOOP macro
#\# #\> (lambda (s c p) (declare (ignore c p)) `(values ,(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
;; This is actually not a trisection but a bisection though I put this here as
;; the goal is the same; it is an alternative of integer trisection.
(declaim (inline trisect-left))
(defun trisect-left (target start end &key maximum)
"TARGET := function | (TODO: vector)
Returns the leftmost index at which TARGET takes the minimum. TARGET must
satisfy the following condition: the signs of TARGET[i+1] - TARGET[i] are
monotone, i.e. -, -, ..., -, 0, 0, ..., 0, +, +, ..., + for i = START, START+1,
..., END-1; convexity or unimodality is sufficient. (If MAXIMUM is true, these
behaviours are so replaced.)
Note that this function searches the optimal value in the **closed** interval
[START, END]."
(when (= start end)
(return-from trisect-left start))
(let ((ng (- start 1))
(ok end))
(if maximum
(loop
(if (<= (- ok ng) 1)
(return ok)
(let ((mid (ash (+ ok ng) -1)))
(if (<= (funcall target (+ 1 mid))
(funcall target mid))
(setq ok mid)
(setq ng mid)))))
(loop
(if (<= (- ok ng) 1)
(return ok)
(let ((mid (ash (+ ok ng) -1)))
(if (>= (funcall target (+ 1 mid))
(funcall target mid))
(setq ok mid)
(setq ng mid))))))))
(declaim (ftype (function * (values fixnum &optional)) read-fixnum))
(defun read-fixnum (&optional (in *standard-input*))
"NOTE: cannot read -2^62"
(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))))))))
(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)))
(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 (inline println))
(defun println (obj &optional (stream *standard-output*))
(let ((*read-default-float-format* 'double-float))
(prog1 (princ obj stream) (terpri stream))))
(defconstant +mod+ 1000000007)
;;;
;;; Body
;;;
(defun main ()
(declare (inline sort))
(let* ((n (read))
(as (make-array n :element-type 'uint31))
(cumul (make-array (+ n 1) :element-type 'uint62 :initial-element 0)))
(declare ((simple-array uint31 (*)) as)
(uint31 n))
(dotimes (i n)
(setf (aref as i) (read-fixnum)))
(setq as (sort as #'<))
(dotimes (i n)
(setf (aref cumul (+ i 1))
(+ (aref cumul i) (aref as i))))
#>cumul
(labels ((calc-odd (pivot width)
(declare (uint31 pivot width)
(values fixnum))
(let ((base (* (aref as pivot) (+ width width 1))))
(- (+ (- (aref cumul n) (aref cumul (- n width)))
(- (aref cumul pivot) (aref cumul (- pivot width)))
(aref as pivot))
base))))
(println
(max 0
(loop for pivot of-type uint31 from 1 below (- n 1)
for width-limit = (min pivot (- n pivot 1))
for opt-width = (trisect-left
(lambda (width)
(declare (uint31 width))
(calc-odd pivot width))
1 width-limit :maximum t)
maximize (calc-odd pivot opt-width)))))))
#-swank (main)
;;;
;;; Test and benchmark
;;;
#+swank
(defun io-equal (in-string out-string &key (function #'main) (test #'equal))
"Passes IN-STRING to *STANDARD-INPUT*, executes FUNCTION, and returns true if
the string output to *STANDARD-OUTPUT* is equal to OUT-STRING."
(labels ((ensure-last-lf (s)
(if (eql (uiop:last-char s) #\Linefeed)
s
(uiop:strcat s uiop:+lf+))))
(funcall test
(ensure-last-lf out-string)
(with-output-to-string (out)
(let ((*standard-output* out))
(with-input-from-string (*standard-input* (ensure-last-lf in-string))
(funcall function)))))))
#+swank
(defun get-clipbrd ()
(with-output-to-string (out)
;; (run-program "C:/Windows/System32/WindowsPowerShell/v1.0/powershell.exe" '("get-clipboard") :output out)
(run-program "powershell.exe" '("-Command" "Get-Clipboard") :output out :search t)))
#+swank (defparameter *this-pathname* (uiop:current-lisp-file-pathname))
#+swank (defparameter *dat-pathname* (uiop:merge-pathnames* "test.dat" *this-pathname*))
#+swank
(defun run (&optional thing (out *standard-output*))
"THING := null | string | symbol | pathname
null: run #'MAIN using the text on clipboard as input.
string: run #'MAIN using the string as input.
symbol: alias of FIVEAM:RUN!.
pathname: run #'MAIN using the text file as input."
(let ((*standard-output* out))
(etypecase thing
(null
(with-input-from-string (*standard-input* (delete #\Return (get-clipbrd)))
(main)))
(string
(with-input-from-string (*standard-input* (delete #\Return thing))
(main)))
(symbol (5am:run! thing))
(pathname
(with-open-file (*standard-input* thing)
(main))))))
#+swank
(defun gen-dat ()
(uiop:with-output-file (out *dat-pathname* :if-exists :supersede)
(format out "")))
#+swank
(defun bench (&optional (out (make-broadcast-stream)))
(time (run *dat-pathname* out)))