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BBc-1 と Ethereum 入門 / Introduction to BBc-1 and...

BBc-1 と Ethereum 入門 / Introduction to BBc-1 and Ethereum

2019年6月5日(火)、ブロックチェーンハブ主催で開催されたブロックチェーンアカデミー「実践!スマートコントラクトプログラミング 第1回 BBc-1 と Ethereum 入門」にて使用したスライドです。

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Kenji Saito

June 05, 2019
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  1. ୈ1ճ BBc-1ͱEthereumೖ໳ ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά ϒϩοΫνΣʔϯϋϒ CSO / ܚጯٛक़େֶ SFC ݚڀॴ ্੮ॴһ

    ੪౻ ݡ࣐ [email protected] ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.1/34
  2. ؆୯ͳࣗݾ঺հ ੪౻ ݡ࣐ (͍͞ͱ͏ ͚Μ͡) ܚጯٛक़େֶ SFC ݚڀॴ ্੮ॴһɾ؀ڥ৘ใֶ෦ ߨࢣ

    (ඇৗۈ) גࣜձࣾϒϩοΫνΣʔϯϋϒ CSO (Chief Science Officer) Ұൠࣾஂ๏ਓϏϤϯυϒϩοΫνΣʔϯ ୅දཧࣄ Ұൠࣾஂ๏ਓΞΧσϛʔΩϟϯϓ ୅දཧࣄ ܦྺ 1993 ೥ɺίʔωϧେֶΑΓ޻ֶम࢜߸औಘ (ίϯϐϡʔλαΠΤϯε) 2006 ೥ɺܚጯٛक़େֶΑΓσδλϧ௨՟ͷݚڀͰത࢜߸औಘ (੓ࡦɾϝσΟΞ) ܚጯٛक़େֶ େֶӃ ੓ࡦɾϝσΟΞݚڀՊ΍ SFC ݚڀॴʹͯ 18 ೥Ҏ্ʹΘͨΓ P2P (Peer-to-Peer) ͓Αͼσδλϧ௨՟౳ͷݚڀʹैࣄ 2011 ೥ՆΑΓ෱ౡͷ͜Ͳ΋ͨͪͷͨΊͷʮΞΧσϛʔΩϟϯϓʯΛ஥ؒΒͱ։࠵ ࡢՆ͸ SFC ʹͯ ΞΧσϛʔΩϟϯϓ 2018 ՆʮΦοέʔάʔάϧɺ॓୊΍ͬͱ͍ͯʂʯΛ࣮ࢪ ࡢౙɺΞΧσϛʔΩϟϯϓ 2019 ౙʮԵঁͷͨΊͷΦʔτϝʔγϣϯ ∼ ΧϫΠΠ͸ࣗಈԽͰ͖ΔʂʯΛ࣮ࢪ → ࢲͷ಄ͷதͰ͸ͭͳ͕͍ͬͯ·͢ (͜Ε͔ΒͷࣾձͷσβΠϯ͸͜Ͳ΋ͨͪͱҰॹʹ) ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.3/34
  3. ࠓճͷςʔϚ ୈ̍ճͱͳΔຊηϛφʔͰ͸ɺ ʮϒϩοΫνΣʔϯͰͰ͖Δͱ͞Ε͍ͯΔ͜ͱΛɺຊ౰ʹʯͷ Ωϟ ονϑϨʔζͰ։ൃ͕ਐΊΒΕ͍ͯΔ BBc-1 (Beyond Blockchain One) ͱɺ

    εϚʔτίϯτϥΫτͷج൫ͱͯ͠஌ΒΕΔ Ethereum Λ ͓खݩͷ؀ڥʹΠϯετʔϧͭͭ͠ɺ ͦΕΒͷج൫ͷ֓೦ʹֶ͍ͭͯͼ·͢ ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.4/34
  4. ࠓճͷߏ੒ 1. Ethereum ௒֓࿦ 2. Ethereum ಋೖ 3. εϚʔτίϯτϥΫτͱ Ethereum

    4. ॓୊ͷग़୊ 5. BBc-1 ௒֓࿦ɺಋೖ͓Αͼςετ ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.5/34
  5. ϒϩοΫνΣʔϯ͸ԿΛఏڙ͢Δٕज़͔ 1) ಺༰΋ଘࡏ΋୭ʹ΋൱ఆͰ͖ͳ͍Α͏ʹه࿥Λอଘɾҡ࣋͢Δ 2) ͦͷ͔֬͞Λ୭Ͱ΋֬ೝͰ͖Δ (= ͔֬ͩͱূ໌Ͱ͖Δ) 3) Ҏ্ͷ͜ͱΛ୭ʹ΋ࢭΊͤ͞ͳ͍ ʮ୭ʹ΋ʯ

    ʮ୭Ͱ΋ʯͱ͸ఆٛ͞ΕͨεςʔΫϗϧμʔͨͪ ⇒ ͔͋ͨ΋ۭதʹه࿥ΛݻఆͰ͖Δ ϓϩάϥϜͱσʔλ΋ͦΜͳ෩ʹͯ͠ݻఆͰ͖Δ (= εϚʔτίϯτϥΫτ) ⇒ ೋॏͷ՝୊͕͋Δ ͦͷ͜ͱ͸ຊ౰ʹ࣮ݱͰ͖͍ͯΔͷ͔ʁ ͦͷ͜ͱ͕࣮ݱͰ͖ͨΒऔΓࠫଡ͞Ε͍ͯΔԠ༻͕Մೳͳͷ͔ʁ ෺ཧత࣮ମͱσδλϧͳه࿥ͱͷؒͷ࣮֬ͳඥ෇͚ͷ໰୊ · αϓϥΠνΣʔϯʹ͓͍ͯ͸ɺՃ޻౳Λܦͯ΋࣮֬ʹ௥੻Մೳ͔ ࣮࣌ؒੑɾن໛֦େ/ॖখੑɾదԠੑɾ࣋ଓੑ౳ͷ՝୊ (dependable ͳ΋ͷʹͳΓಘΔͷ͔) ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.7/34
  6. ϒϩοΫνΣʔϯ/DLT ͷݱঢ় ϒϩοΫνΣʔϯ (ओͱͯ͠ʮۭதʯ͸άϩʔόϧ) Bitcoin (βɾϒϩοΫνΣʔϯ) Open Assets Protocol (OAP)

    (ϏοτίΠϯϒϩοΫνΣʔϯ্ʹ೚ҙͷྔΛఆٛͯ͠ҠసͰ͖Δ) Ethereum (Dapps (ۭதͰಈ࡞͢ΔΞϓϦ) ͷͨΊͷج൫) (ଟ෼ʹ࣮ݧγεςϜ) EOS (↓ ͬͪ͜ํ޲΁ͷਐԽʁ) ͦͷଞͷ୆ாٕज़ (DLT) (ओͱͯ͠ʮۭதʯ͸ϩʔΧϧ) Hyperledger (Linux Foundation) Fabric (IBM/DAH), Sawtooth (Intel), Iroha (ιϥϛπ) ͳͲͷ։ൃ͕ਐߦத Corda (R3), . . . , BBc-1 (զʑ) ຊ౰ʹه࿥ͷ಺༰΋ଘࡏ΋୭ʹ΋൱ఆͰ͖ͳ͍ͷ͔ʁ ຊ౰ʹه࿥ͷ ͔֬͞Λ୭Ͱ΋֬ೝͰ͖Δ ͱݴ͑Δͷ͔ʁ ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.8/34
  7. Ethereum ͱ͸ʁ Vitalik Buterin, “Ethereum White Paper: A NEXT GENERATION

    SMART CONTRACT & DECENTRALIZED APPLICATION PLATFORM” ϒϩοΫνΣʔϯٕज़ΛԠ༻ ฏۉϒϩοΫִؒ໿ 15 ඵ ͦ͜ʹϓϩάϥϛϯάݴޠΛࡌͤΔ νϡʔϦϯά׬શ Dapps (୤தԝΞϓϦ/ۭதͰಈ࡞͢ΔΞϓϦ/தԝΛࣗಈԽ͢ΔΞϓϦ) ͷͨΊͷج൫ ݱࡏͷۚ༥ɾ՟ฎܦࡁγεςϜΛ࣌୅஗Εʹ͠Α͏ͱ͢Δҙਤ͕ݟ͑Δ εϚʔτίϯτϥΫτͱ͸ͦ΋ͦ΋ͦ͏͍͏΋ͷ ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.9/34
  8. 2. Ethereum ಋೖ ڭࡐ͸࣍ͷ؀ڥͰςετ͍ͯ͠·͢ macOS (Mojave 10.14.5) + Homebrew Linux

    (Ubuntu 16.04) Windows 10 + Windows Subsystem for Linux (Ubuntu 16.04 ͱͯ͠ςετ) Ethereum ؀ڥͱͯ͠ solidity ͓Αͼ brownie Λ࢖༻͠·͢ ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.10/34
  9. Solidity ͷΠϯετʔϧ Ethereum ͷεϚʔτίϯτϥΫτͷ։ൃݴޠͰ͢ Πϯετʔϧํ๏ http://solidity.readthedocs.io/en/latest/installing-solidity.html Linux (on Windows) Ͱ͸

    “sudo apt”, macOS Ͱ͸ “brew” ͰͷΠϯετʔϧͰ͢ solc 0.5.9 ͕Πϯετʔϧ͞Ε·͢ (6/5 ݱࡏ) ࣮ߦͰ͖Δ͜ͱΛ֬ೝ͠·͢ $ solc --version Πϯετʔϧ͞ΕͨόʔδϣϯΛ֬ೝͯ͠Έ·͠ΐ͏ ࠓճɺ࣮ࡍʹ࢖༻͢ΔίϯύΠϥ͸ brownie ͱҰॹʹΠϯετʔϧ͞ΕΔ py-solc-x Ͱ͕͢ɺ solc ͕ґଘ͢Δ؀ڥ (dependencies) ͕ඞཁͱͳΓ·͢ (ద੾ͳ solc ίϯύΠϥΛ py-solc-x ͕Πϯετʔϧ͠·͢) ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.11/34
  10. Python3 ͷΠϯετʔϧ macOS ͷ৔߹ $ brew install python3 Linux ͷ৔߹

    $ sudo add-apt-repository ppa:deadsnakes/ppa $ sudo apt update $ sudo apt install python3.7 python3.7-dev python3.7-venv python3.7-tk 16.10 Ҏ߱ͷ൛Ͱ͸ python3(.7) Λͦͷ·· apt ͰΠϯετʔϧͰ͖·͢ɻ ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.12/34
  11. macOS : ΋͠Ҏ߱ͷεςοϓͰ . . . macOS ʹ wget ͕ͳ͍ͱݴΘΕͨ৔߹ɺbrew

    ͰΠϯετʔϧ͍ͯͩ͘͠͞ ·͋ɺແ͚Ε͹ࠓೖΕͪΌ͑͹Α͍Ͱ͢ΑͶ ͞Βʹ dyld: Library not loaded: /usr/local/opt/gettext/lib/libintl.8.dylib ͷΑ͏ʹͳΔ৔߹͸ɺҎԼΛࢼͯ͠Έ͍ͯͩ͘͞ $ brew uninstall --force gettext $ brew install gettext ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.13/34
  12. Python Ծ૝؀ڥ (venv) macOS ͷ৔߹͸ ‘python3.7’ Λ ‘python3’ ͱಡΈସ͍͑ͯͩ͘͞ $

    python3.7 -m venv bbc1env $ source bbc1env/bin/activate (bbc1env) $ pip install -U pip bbc1env (ࠓޙ BBc-1 ΛΠϯετʔϧ͢ΔͨΊ) ͱ͍͏Ծ૝؀ڥΛͭ͘Γ·ͨ͠ ௨ৗͷ࡞ۀ͸Ծ૝؀ڥ಺Ͱߦ͍·͢ Ծ૝؀ڥ͔Βग़Δ৔߹͸࣍ͷίϚϯυΛ༻͍·͢ (ࠓ͸ग़·ͤΜ) (bbc1env) $ deactivate ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.14/34
  13. Ganache CLI ͷΠϯετʔϧ Ethereum ͷ RPC ΫϥΠΞϯτͰ͋Γςετ؀ڥͰ͢ ·ͣ npm ΛΠϯετʔϧ͠·͢

    (͓࢖͍Ͱͳ͍৔߹) macOS ͷ৔߹ https://qiita.com/PolarBear/items/62c0416492810b7ecf7c Λ͝ࢀߟʹ Linux ͷ৔߹ https://qiita.com/seibe/items/36cef7df85fe2cefa3ea Λ͝ࢀߟʹ ͦͯ͠ npm Λ࢖ͬͯ Ganache CLI ΛΠϯετʔϧ͠·͢ $ sudo npm install -g ganache-cli ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.15/34
  14. Brownie ͷΠϯετʔϧ Python ʹΑΔ Ethereum ͷ։ൃɾςετ؀ڥͰ͢ https://eth-brownie.readthedocs.io Brownie ΛΠϯετʔϧ͠·͢ $

    pip install eth-brownie version 1.0.0b7 ͕Πϯετʔϧ͞Ε·͢ (6/5 ݱࡏ) ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.16/34
  15. ϓϩδΣΫτͷॳظԽ ৽͍͠ϓϩδΣΫτΛͭ͘Γ·͢ $ brownie init ࣮ߦ৔ॴΛج఺ͱͯ͠σΟϨΫτϦߏ଄͕࡞ΒΕ·͢ Ͱ͕͢ࠓճ͸طଘͷςϯϓϨʔτΛ࢖ͬͯΈ·͠ΐ͏ (؆қͳ ERC-20 ࣮૷Ͱ͢)

    $ brownie bake token $ cd token ίϯύΠϧ͠·͢ (ίϯτϥΫτͷίʔυΛͪΐͬ͜ͱݟͯΈ·͠ΐ͏) $ brownie compile ςετ͠·͢ (ςετίʔυΛͪΐͬ͜ͱݟͯΈ·͠ΐ͏) $ brownie test ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.17/34
  16. ίϯιʔϧΛ࢖ͬͯΈ·͠ΐ͏ Brownie ͷίϯιʔϧΛ࢖ͬͯɺςετ؀ڥͷঢ়ଶΛݟͯΈ·͢ $ brownie console Ҏ߱ɺPython ΠϯλϓϦλͰૢ࡞Ͱ͖·͢ >>> len(accounts)

    10 >>> accounts[0].balance() 100000000000000000000 >>> quit() ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.18/34
  17. ༻ޠମܥ Ether Ethereum ʹ͓͚Δ௨՟ ֎෦ΞΫλʔ σδλϧॺ໊Ͱ͖Δ࣮ࡏͰɺΞΧ΢ϯτΛ΋ͭ EOA : Externally-Owned Account

    ࣗ཯ΦϒδΣΫτ γεςϜ಺Ͱࣗ཯ಈ࡞͠ɺΞΧ΢ϯτΛ΋ͭ ΞΧ΢ϯτ Ether ࢒ߴΛ΋ͪɺετϨʔδ΍ EVM ίʔυΛ΋ͯΔ EVM ίʔυ εϚʔτίϯτϥΫτͷϓϩάϥϜ ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.24/34
  18. ϓϩάϥϛϯάݴޠ EVM ͕ղऍ͢Δͷ͸όΠτίʔυ ͦͷଞʹߴڃݴޠͷίϯύΠϥΛ༻ҙ ߴڃݴޠ : ਓ͕ؒಡΈॻ͖Ͱ͖Δݴޠ ྫ : Solidity

    — JavaScript ʹࣅͨݴޠ ݱࡏͷϓϥΠϚϦݴޠ LLL — Lisp ʹࣅͨݴޠ ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.26/34
  19. Solidity αϯϓϧίʔυ (͜Ε͕ߴڃݴޠͩʂ) pragma solidity ˆ0.4.24; contract IndivisibleAsset { /*

    ෼ׂͰ͖ͳ͍ࢿ࢈ͷॴ༗ݖͷҠసΛ࣮ݱ */ string public _name; string public _symbol; uint256 public _quantity; address public _owner; constructor (string name, string symbol, uint256 quantity) public { _name = name; _symbol = symbol; _quantity = quantity; _owner = msg.sender; } function transfer(address to) external returns (bool) { require(_owner == msg.sender); _owner = to; return true; } } ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.27/34
  20. ಛ௃ͱ՝୊ ಛ௃ ϒϩοΫͷݕূͷաఔͰϓϩάϥϜΛ࣮ߦ͠ɺ ͦͷ݁ՌΛঢ়ଶʹ൓өͤ͞Δ ෳ਺ͷݕূऀ͕৑௕ʹ࣮ߦ ϒϩοΫνΣʔϯͷதʹด͡Δ Ethereum ͷମܥͷதͰ͸੔߹త ՝୊ ϓϩάϥϜͷத͔Βೖग़ྗίϚϯυΛग़ͤͳ͍

    ֎෦ΞΫλʔҎ֎ͷ֎քͷӨڹΛड͚ͨΓɺ ֎քʹ௚઀ӨڹΛٴ΅͢͜ͱ͕Ͱ͖ͳ͍ ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.28/34
  21. infura.io ΞΧ΢ϯτऔಘͱ Brownie ͷઃఆ https://infura.io ʹ SIGN UP ͯ͠ɺPROJECT ID

    Λऔಘ͍ͯͩ͘͠͞ infura ͸ Ethereum ϑϧϊʔυͷػೳΛ API Ͱఏڙ͢ΔαʔϏεͰ͢ ։ൃ΍࣮ݧʹ͸Α͍Ͱ͕͢ɺϓϩμΫτʹ͸࢖͑ͳ͍ͱߟ͓͖͑ͯ·͠ΐ͏ infura.io ͷࣗ͝਎ͷϓϩδΣΫτϖʔδ͔Βɺ ROPSTEN ༻ͷ ENDPOINT Λίϐʔ͍ͯͩ͘͠͞ ͓खݩͷ Brownie ͷϓϩδΣΫτͷ “brownie-config.json” Λฤू͠·͢ “networks” ͷதͷ “ropsten” ͷ “host” URL ͷ “ropsten.∼” ҎԼΛɺ ίϐʔͨ͠ ENDPOINT Ͱ্ॻ͖͍ͯͩ͘͠͞ ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.30/34
  22. ropsten ΞΧ΢ϯτͷ࡞੒ͱ ETH ͷऔಘ brownie console Λ༻͍ͯ ropsten ༻ͷΞΧ΢ϯτΛ࡞੒͠·͢ >>>

    network.disconnect() >>> network.connect(’ropsten’) >>> len(accounts) 0 >>> accounts.add() <LocalAccount object ’ ͜͜ʹΞΧ΢ϯτͷ 16 ਐ਺จࣈྻ͕දࣔ͞Ε·͢’> >>> accounts[0].private_key ͜͜ʹΞΧ΢ϯτͷൿີݤͷ 16 ਐ਺จࣈྻ͕දࣔ͞Ε·͢ >>> quit() ॏཁʂΞΧ΢ϯτͱൿີݤΛͦΕͧΕίϐʔͯ͠อ؅͠·͠ΐ͏ʂ Ropsten Ethereum Faucet ͔Β 1ETH Λऔಘ͍ͯͩ͘͠͞ https://faucet.ropsten.be ʹΞΫηε͠ɺ ΞΧ΢ϯτ (ൿີݤͰ͸͋Γ·ͤΜ) Λೖྗ͠·͢ ͏·͍͔͘ͳ͍৔߹͸ https://metamask.io/Λར༻͢Δํ๏౳΋͋Γ·͢ͷͰɺௐ΂ͯࢼͯ͠Έ͍ͯͩ͘͞ ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.31/34
  23. ropsten ETH ࢒ߴͷ֬ೝ brownie console Λ༻͍ͯ ropsten ༻ͷ ETH ࢒ߴΛ֬ೝ͠·͢

    >>> network.disconnect() >>> network.connect(’ropsten’) >>> len(accounts) 0 >>> accounts.add(͜͜ʹൿີݤͷ 16 ਐ਺จࣈྻΛϖʔετ͍ͯͩ͘͠͞) <LocalAccount object ’ ͜͜ʹΞΧ΢ϯτͷ 16 ਐ਺จࣈྻ͕දࣔ͞Ε·͢’> >>> accounts[0].balace() ͜͜ʹΞΧ΢ϯτͷ ETH ࢒ߴ͕දࣔ͞Ε·͢ >>> quit() Ҏ্Λ࣍ճ·Ͱʹ͓ئ͍͍ͨ͠·͢ʂ ࣮ફʂεϚʔτίϯτϥΫτϓϩάϥϛϯά — ୈ 1 ճ BBc-1 ͱ Ethereum ೖ໳ — 2019-06-05 – p.32/34