前回の”どう書く”を もっと高速にしてみた 2019.4.17 Nagoya.php #15

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1. લճͷ”Ͳ͏ॻ͘”Λ ΋ͬͱߴ଎ʹͯ͠Έͨ 2019.4.17 Nagoya.php #15
2. ·ͣ͸ࣗݾ঺հ
3. ͱ͋Δాࣷͷphper @inaka_phper phpྺ16೥(࣮ྗ͕൐͍ͬͯΔ͔͸ผ) 3೥લʹ۽ຊ͔Β໊ݹ԰΁స৬͖ͯ͠·ͨ͠ɻ 4ࡀࣇͱ1ࡀࣇͷ෕
 ՈͰͷझຯ։ൃ͢Δ࣌ؒΛͲ͏೧ग़͢Δ͔͕࠷ۙͷ೰Έ
4. લճͷ໰୊Λ͓͞Β͍
5. IUUQOBCFUBOJTBLVSBOFKQIFOBPSEFQBMJO
6. ૉ௚ʹղ͍ͯ΋… public function run(string $input): int { $args = explode(",", $input); $start = (int)$args[0]; $end = (int)$args[1]; $tobase = (int)$args[2]; $visibleCounter = 0; for ($i = $start; $i < $end; $i++) { $number = base_convert($i, 10, $tobase); if ($number === strrev($number)) { $visibleCounter++; } } return $visibleCounter; }
7. λΠϜΞ΢τ phper:NagoyaPhp14 phper$ composer test > vendor/bin/phpunit PHPUnit 7.5.7 by Sebastian Bergmann and contributors. ...................... [Symfony\Component\Process\Exception\ProcessTimedOutException] The process "vendor/bin/phpunit" exceeded the timeout of 300 seconds.
8. λΠϜΞ΢τͷݪҼ ['12345,987654321,2', 62684], ['2467130,8433468,2', 2902], ['323901,4712975,10', 4389], ['12345,987654321,36', 67446], ['3969344,4086910,24', 205], ['19743263,83912295,5', 11553], ['6349529,39870823,10', 6637], ['66160071,153732445,5', 5605], ['18799557,189007582,14', 33741], ['78547566,225312226,20', 18346], ['143084571,506549072,18', 62323], ['2099642384,2789567569,6', 14787], ࢦఆͷςετέʔεͰ͸َϧʔϓ͕ൃੜ͢Δ
9. ߴ଎Խ͢Δʹ͸ ϧʔϓΛݶք·ͰݮΒ͢͜ͱ
10. IUUQTTQFBLFSEFDLDPNUUTLDIKJOSJGBMTFUPVTIVLVXFOUJGBMTFBSVLPSJTVNVMJ TMJEF Ҏ߱ɺ్த·Ͱ͖ͨͭͪ͞ΜͱҰॹ
11. લճɺ୭΋͕ࢥͬͨ͸ͣ… ܭࢉͰग़དྷΔͷͰ͸ʁ
12. ݕূͨ݁͠Ռ
13. ܭࢉͰ͍͚·ͨ͠ɻ
14. ςετέʔε݁Ռ phper:NagoyaPhp14 phper$ composer test > vendor/bin/phpunit PHPUnit 7.5.7 by Sebastian Bergmann and contributors. .................................. 34 / 34 (100%) Time: 47 ms, Memory: 4.00 MB OK (34 tests, 34 assertions) phper:NagoyaPhp14 phper$
15. υϠΝʂʂ phper:NagoyaPhp14 phper$ composer test > vendor/bin/phpunit PHPUnit 7.5.7 by Sebastian Bergmann and contributors. .................................. 34 / 34 (100%) Time: 47 ms, Memory: 4.00 MB OK (34 tests, 34 assertions) phper:NagoyaPhp14 phper$
16. Ͳ͏ܭࢉͨ͠ͷ͔ʁ
17. 10000-99999ͰճจͱͳΔ਺஋ Λग़ྗͯ͠๏ଇΛ୳Δ (10ਐ਺)
18. 10000-99999ͰճจΛग़ྗ 10101 10201 10301 10401 10501 10601 10701 10801 10901 11011 11111 11211 11311 11411 11511 11611 11711 11811 11911 12021 … 99099 99199 99299 99399 99499 99599 99699 99799 99899
19. 10000-99999ͰճจΛग़ྗ 10101 10201 10301 10401 10501 10601 10701 10801 10901 11011 11111 11211 11311 11411 11511 11611 11711 11811 11911 12021 … 99099 99199 99299 99399 99499 99599 99699 99799 99899 ࠨ൒෼ͷ਺஋͕ͭͣͭ૿͑ͯΔ
20. ࠷ޙ - ։࢝ = ճจग़ݱ਺
21. ࠷ޙ 99999 ࠷ॳ 10000 999 - 100 = 899
23. ߟྀ͢΂͖έʔε
24. ૝ఆ͞ΕΔߟྀ͠ͳ͍ͱ͍͚ ͳ͍ࣄ 1. php͸nਐ਺ͷ··ܭࢉͰ͖ͳ͍ 2. ӈ൒෼ͷ։࢝ɾ࠷ޙͷҐஔʹΑͬͯޡ͕ࠩ ग़Δ 3. ح਺͔Βۮ਺΁ͷ܁Γ্͕Γͷࠨ൒෼…
25. php ͸nਐ਺ͷ··ܭࢉͰ͖ ͳ͍ ໘౗͕ͩม׵͠௚ͯ͠ճආ 1. ࢦఆͷnਐ਺΁ม׵ 2. ࠨ൒෼Λ੾Γग़͢ 3. ੾Γग़ͨ͠ࠨ൒෼Λ10ਐ਺΁ 255 -> ff ff -> f f -> 15
26. ӈ൒෼ͷ։࢝ɾ࠷ޙͷҐஔʹ Αͬͯޡ͕ࠩग़Δ 10000ͷࠨ൒෼ 10099ͷࠨ൒෼ ಉ͡100͕ͩޙऀ͸10001͕੒ཱ͠ͳ͍ ࠷ॳͱ࠷ޙ͸ࠨ൒෼ͷճจͷൣғ಺͔νΣοΫ
27. ح਺͔Βۮ਺΁ͷ܁Γ্͕Γ ͷࠨ൒෼… 10000 … 99999 100000 ܁Γ্͕ͬͨͷʹࠨ൒෼͚ͩͰݟΔͱॳظ஋ʹ໭ͬͯ͠·͏ ͜ͷλΠϛϯάͰҰ୴ 999 - 100Λͯ݁͠ՌΛੵΈ্͛ͯճආ
28. ͜ΕΒͷରࡦͰ όονϦͰͨ͠