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This file is part of Logtalk https://logtalk.org/ SPDX-FileCopyrightText: 1998-2023 Paulo Moura <pmoura@logtalk.org> SPDX-License-Identifier: Apache-2.0

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

% start by loading the example:

| ?- logtalk_load(clp_swipl(loader)). ...

% change the default term writing depth (SWI-Prolog 7.1.10 or earlier):

| ?- set_prolog_flag(toplevel_print_options, [quoted(true), portray(true), max_depth(50), priority(699)]). true.

% change the default term writing depth (SWI-Prolog 7.1.11 or later):

| ?- set_prolog_flag(answer_write_options, [quoted(true), portray(true), max_depth(50), priority(699)]). true.

| ?- puzzle::solve(Sum=Rs). Sum = [9, 5, 6, 7]+[1, 0, 8, 5], Rs = [1, 0, 6, 5, 2] .

| ?- hexagon::mhex(Vs). Vs = [3, 17, 18, 19, 7, 1, 11, 16, 2, 5, 6, 9, 12, 4, 8, 14, 10, 13, 15] ; Vs = [3, 19, 16, 17, 7, 2, 12, 18, 1, 5, 4, 10, 11, 6, 8, 13, 9, 14, 15] ; Vs = [9, 11, 18, 14, 6, 1, 17, 15, 8, 5, 7, 3, 13, 4, 2, 19, 10, 12, 16] ; (etc)

| ?- soduku::sudoku(Rows), append(Rows, Vs), label(Vs). Rows = [[1, 2, 3, 4, 5, 6, 7, 8, 9], [4, 5, 6, 7, 8, 9, 1, 2, 3], [7, 8, 9, 1, 2, 3, 4, 5, 6], [2, 1, 4, 3, 6, 5, 8, 9, 7], [3, 6, 5, 8, 9, 7, 2, 1, 4], [8, 9, 7, 2, 1, 4, 3, 6, 5], [5, 3, 1, 6, 4, 2, 9, 7, 8], [6, 4, 2, 9, 7, 8, 5, 3, 1], [9, 7, 8, 5, 3, 1, 6, 4, 2]], Vs = [1, 2, 3, 4, 5, 6, 7, 8, 9, 4, 5, 6, 7, 8, 9, 1, 2, 3, 7, 8, 9, 1, 2, 3, 4, 5, 6, 2, 1, 4, 3, 6, 5, 8, 9, 7, 3, 6, 5, 8, 9, 7, 2, 1, 4, 8, 9, 7, 2|...] ; Rows = [[1, 2, 3, 4, 5, 6, 7, 8, 9], [4, 5, 6, 7, 8, 9, 1, 2, 3], [7, 8, 9, 1, 2, 3, 4, 5, 6], [2, 1, 4, 3, 6, 5, 8, 9, 7], [3, 6, 5, 8, 9, 7, 2, 1, 4], [8, 9, 7, 2, 1, 4, 3, 6, 5], [5, 3, 1, 6, 4, 2, 9, 7, 8], [6, 4, 8, 9, 7, 1, 5, 3, 2], [9, 7, 2, 5, 3, 8, 6, 4, 1]], Vs = [1, 2, 3, 4, 5, 6, 7, 8, 9, 4, 5, 6, 7, 8, 9, 1, 2, 3, 7, 8, 9, 1, 2, 3, 4, 5, 6, 2, 1, 4, 3, 6, 5, 8, 9, 7, 3, 6, 5, 8, 9, 7, 2, 1, 4, 8, 9, 7, 2|...] ; (etc)

| ?- soduku::(problem(1, Rows), sudoku(Rows)), append(Rows, Vs), label(Vs). Rows = [[1, 5, 6, 8, 9, 4, 3, 2, 7], [9, 2, 8, 7, 3, 1, 4, 5, 6], [4, 7, 3, 2, 6, 5, 9, 1, 8], [3, 6, 2, 4, 1, 7, 8, 9, 5], [7, 8, 9, 3, 5, 2, 6, 4, 1], [5, 1, 4, 9, 8, 6, 2, 7, 3], [8, 3, 1, 5, 4, 9, 7, 6, 2], [6, 9, 7, 1, 2, 3, 5, 8, 4], [2, 4, 5, 6, 7, 8, 1, 3, 9]], Vs = [1, 5, 6, 8, 9, 4, 3, 2, 7, 9, 2, 8, 7, 3, 1, 4, 5, 6, 4, 7, 3, 2, 6, 5, 9, 1, 8, 3, 6, 2, 4, 1, 7, 8, 9, 5, 7, 8, 9, 3, 5, 2, 6, 4, 1, 5, 1, 4, 9|...] .

% the following two queries implies that Ghostscript is available from the command-line:

| ?- soduku::(problem(1, Rows), show([ff], Rows)). Rows = [[1, 5, 6, 8, 9, 4, 3, 2, 7], [9, 2, 8, 7, 3, 1, 4, 5, 6], [4, 7, 3, 2, 6, 5, 9, 1, 8], [3, 6, 2, 4, 1, 7, 8, 9, 5], [7, 8, 9, 3, 5, 2, 6, 4, 1], [5, 1, 4, 9, 8, 6, 2, 7, 3], [8, 3, 1, 5, 4, 9, 7, 6, 2], [6, 9, 7, 1, 2, 3, 5, 8, 4], [2, 4, 5, 6, 7, 8, 1, 3, 9]] .

| ?- soduku::show([ff], Rows). Rows = [[1, 2, 3, 4, 5, 6, 7, 8, 9], [4, 5, 6, 7, 8, 9, 1, 2, 3], [7, 8, 9, 1, 2, 3, 4, 5, 6], [2, 3, 1, 6, 7, 4, 8, 9, 5], [8, 7, 5, 9, 1, 2, 3, 6, 4], [6, 9, 4, 5, 3, 8, 2, 1, 7], [3, 1, 7, 2, 6, 5, 9, 4, 8], [5, 4, 2, 8, 9, 7, 6, 3, 1], [9, 6, 8, 3, 4, 1, 5, 7, 2]] ; Rows = [[1, 2, 3, 4, 5, 6, 7, 8, 9], [4, 5, 6, 7, 8, 9, 1, 2, 3], [7, 8, 9, 1, 2, 3, 4, 5, 6], [2, 3, 1, 6, 7, 4, 8, 9, 5], [8, 7, 5, 9, 1, 2, 3, 6, 4], [6, 9, 4, 5, 3, 8, 2, 1, 7], [3, 1, 7, 2, 6, 5, 9, 4, 8], [5, 4, 8, 3, 9, 1, 6, 7, 2], [9, 6, 2, 8, 4, 7, 5, 3, 1]] ; Rows = [[1, 2, 3, 4, 5, 6, 7, 8, 9], [4, 5, 6, 7, 8, 9, 1, 2, 3], [7, 8, 9, 1, 2, 3, 4, 5, 6], [2, 3, 1, 6, 7, 4, 8, 9, 5], [8, 7, 5, 9, 1, 2, 3, 6, 4], [6, 9, 4, 5, 3, 8, 2, 1, 7], [3, 1, 7, 2, 6, 5, 9, 4, 8], [9, 6, 2, 8, 4, 7, 5, 3, 1], [5, 4, 8, 3, 9, 1, 6, 7, 2]] ; (etc)

| ?- queens::n_queens(8, Qs), labeling([ff], Qs). Qs = [1, 5, 8, 6, 3, 7, 2, 4] ; Qs = [1, 6, 8, 3, 7, 4, 2, 5] ; Qs = [1, 7, 4, 6, 8, 2, 5, 3] ; (etc)

% the following queries require that Ghostscript is available from the command-line:

| ?- queens::show(8, [ff], Qs). Qs = [1, 5, 8, 6, 3, 7, 2, 4] ; Qs = [1, 6, 8, 3, 7, 4, 2, 5] ; Qs = [1, 7, 4, 6, 8, 2, 5, 3] ; (etc)

| ?- queens::show(N, [ff], Qs). N = 1, Qs = [1] ; N = 4, Qs = [2, 4, 1, 3] ; N = 4, Qs = [3, 1, 4, 2] ; N = 5, Qs = [1, 3, 5, 2, 4] ; (etc)

| ?- oneground::oneground(X, Y, Z), Y = 5. Y = 5, Z = 1, X in inf..sup.

| ?- knight::n_tour(N, Ts), meta::map(clpfd:label, Ts). N = 0, Ts = [] ; N = 6, Ts = [[9, 10, 7, 8, 16, 17], [15, 19, 5, 6, 3, 4], [2, 1, 26, 12, 21, 29], [32, 31, 25, 18, 34, 11], [14, 13, 35, 36, 33, 22], [27, 28, 20, 30, 24, 23]] .

| ?- knight::n_tour(6, Ts), meta::map(label, Ts), knight::tour_enumeration(Ts, Es), meta::map(format("~t~w~3|~t~w~6|~t~w~9|~t~w~12|~t~w~15|~t~w~18|\n"), Es). 1 30 25 6 3 32 26 7 2 31 24 5 29 36 27 4 33 16 8 19 34 15 12 23 35 28 21 10 17 14 20 9 18 13 22 11 Ts = [[9, 10, 7, 8, 16, 17], [15, 19, 5, 6, 3, 4], [2, 1, 26, 12, 21, 29], [32, 31, 25, 18, 34, 11], [14, 13, 35, 36, 33, 22], [27, 28, 20, 30, 24, 23]], Es = [[1, 30, 25, 6, 3, 32], [26, 7, 2, 31, 24, 5], [29, 36, 27, 4, 33, 16], [8, 19, 34, 15, 12, 23], [35, 28, 21, 10, 17, 14], [20, 9, 18, 13, 22, 11]] .

| ?- time((knight::n_tour(8, Ts), list::append(Ts, Vs), clpfd:labeling([ff], Vs))). % 18,438,711 inferences, 4.230 CPU in 4.482 seconds (94% CPU, 4359033 Lips) Ts = [[11, 12, 18, 10, 15, 21, 13, 14], [3, 20, 17, 27, 23, 31, 30, 6], [2, 1, 29, 5, 4, 37, 8, 7], [19, 9, 33, 38, 35, 36, 16, 22], [43, 28, 50, 51, 52, 32, 24, 46], [26, 25, 53, 59, 55, 61, 62, 54], [34, 60, 57, 58, 63, 64, 40, 39], [42, 41, 49, 45, 44, 56, 48, 47]], Vs = [11, 12, 18, 10, 15, 21, 13, 14, 3, 20, 17, 27, 23, 31, 30, 6, 2, 1, 29, 5, 4, 37, 8, 7, 19, 9, 33, 38, 35, 36, 16, 22, 43, 28, 50, 51, 52, 32, 24, 46, 26, 25, 53, 59, 55, 61, 62, 54, 34|...].

| ?- knight::n_tour(8, Ts), list::append(Ts, Vs), clpfd:labeling([ff], Vs), knight::tour_enumeration(Ts, Es), meta::map(format("~t~w~3|~t~w~6|~t~w~9|~t~w~12|~t~w~15|~t~w~18|~t~w~21|~t~w~24|\n"), Es). 1 4 63 28 31 26 19 22 62 29 2 5 20 23 32 25 3 64 39 30 27 56 21 18 38 61 6 53 40 33 24 55 7 52 41 34 57 54 17 46 60 37 8 49 44 47 14 11 51 42 35 58 9 12 45 16 36 59 50 43 48 15 10 13 Ts = [[11, 12, 18, 10, 15, 21, 13, 14], [3, 20, 17, 27, 23, 31, 30, 6], [2, 1, 29, 5, 4, 37, 8, 7], [19, 9, 33, 38, 35, 36, 16, 22], [43, 28, 50, 51, 52, 32, 24, 46], [26, 25, 53, 59, 55, 61, 62, 54], [34, 60, 57, 58, 63, 64, 40, 39], [42, 41, 49, 45, 44, 56, 48, 47]], Vs = [11, 12, 18, 10, 15, 21, 13, 14, 3, 20, 17, 27, 23, 31, 30, 6, 2, 1, 29, 5, 4, 37, 8, 7, 19, 9, 33, 38, 35, 36, 16, 22, 43, 28, 50, 51, 52, 32, 24, 46, 26, 25, 53, 59, 55, 61, 62, 54, 34|...], Es = [[1, 4, 63, 28, 31, 26, 19, 22], [62, 29, 2, 5, 20, 23, 32, 25], [3, 64, 39, 30, 27, 56, 21, 18], [38, 61, 6, 53, 40, 33, 24, 55], [7, 52, 41, 34, 57, 54, 17, 46], [60, 37, 8, 49, 44, 47, 14, 11], [51, 42, 35, 58, 9, 12, 45, 16], [36, 59, 50, 43, 48, 15, 10, 13]] .

% the following queries require that Ghostscript is available from the command-line:

| ?- knight::n_tour(6, Ts), meta::map(clpfd:label, Ts), knight::show(Ts).

| ?- knight::n_tour(8, Ts), meta::map(clpfd:label, Ts), knight::show(Ts).