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[爆卦]serial number是什麼是什麼？優點缺點精華區懶人包

雖然這篇serial number是什麼鄉民發文沒有被收入到精華區：在serial number是什麼這個話題中，我們另外找到其它相關的精選爆讚文章

在 serial產品中有2140篇Facebook貼文，粉絲數超過14萬的網紅Focus Taiwan，也在其Facebook貼文中提到， Any luck with winning at least NT$200 this time? A total of four uniform invoices issued in July and August had the winning serial number drawn Saturd...

　同時也有1595部Youtube影片，追蹤數超過14萬的網紅FOS / エフオーエス，也在其Youtube影片中提到，Part3。またシャワーシーンあるんかい 前回→https://youtu.be/VjK43BETu58 【チャンネル登録】https://goo.gl/y3g6PB 《他各チャンネル》 【FOS/生放送】https://is.gd/f1qGyx 【FOS黒のゲーム実況チャンネル】https:...

「serial」的推薦目錄

serial 在 華道家 大谷美香 Ikebana Artist Mika Instagram 的精選貼文

2021-09-24 15:08:48

#プロミスシンデレラ 打ち合わせ用でいけた花今日 Ikebana with dried and Painted flower Materials for shooting! 大女将役である三田佳子さんがいける花をどんな花にしたらいいのか、事前に監督さんたちとスタジオで打ち合わせ。そのときの花です。...

serial 在 華道家 大谷美香 Ikebana Artist Mika Instagram 的精選貼文

2021-09-16 08:33:03

#プロミスシンデレラ いよいよ今日が最終回 Ikebana with dried and Painted flower Materials for shooting! 片岡家の執事 吉寅こと#高橋克実 さんと撮影後に記念撮影。主人が何度もお仕事でご一緒させて頂いてお世話になっている克実さんのところ...

  • Focus Taiwan

    serial 在 Focus Taiwan Facebook 的最讚貼文

    2021-09-26 18:20:02
    有 1,471 人按讚

    Any luck with winning at least NT$200 this time? A total of four uniform invoices issued in July and August had the winning serial number drawn Saturday in the bimonthly lottery draw for the top prize of NT$10 million (US$359,912).
    https://focustaiwan.tw/business/202109260007

  • fanpage พระมหาสมปอง ตาลปุตฺโต

    serial 在 fanpage พระมหาสมปอง ตาลปุตฺโต Facebook 的最讚貼文

    2021-09-26 16:59:55
    有 4,860 人按讚

    #ฟังพระมหาสมปอง เล่าข่าวกรณี
    ศูนย์บำบัดยาเสพติด
    ทุบตีผู้ป่วย-รีดเงินครึ่งแสน!

    รับชมพระมหาสมปอง เล่าข่าวธรรมะพร้อมให้ข้อคิด สอนหลักธรรมเต็มๆได้ใน รายการเจริญพรนิวส์ ได้ที่ https://aisplay.ais.co.th/portal/serial/series/614f4638989f4ae321cc1fa6

    #AISPLAY #PLAYNEWS #พระมหาสมปอง #เจริญพรนิวส์ #ผู้ป่วย #ศูนย์บำบัดยาเสพติด #ข้อคิด #ธรรมะสุขใจ

  • Taipei Ethereum Meetup

    serial 在 Taipei Ethereum Meetup Facebook 的最佳貼文

    2021-09-23 21:53:53
    有 6 人按讚

    📜 [專欄新文章] Gas Efficient Card Drawing in Solidity

    ✍️ Ping Chen

    📥 歡迎投稿： https://medium.com/taipei-ethereum-meetup #徵技術分享文 #使用心得 #教學文 #medium

    Assign random numbers as the index of newly minted NFTs

    Scenario

    The fun of generative art NFT projects depends on randomness. The industry standard is “blind box”, where both the images’ serial number and the NFTs’ index are predetermined but will be shifted randomly when the selling period ends. (They call it “reveal”) This approach effectively solves the randomness issue. However, it also requires buyers to wait until the campaign terminates. What if buyers want to know the exact card right away? We’ll need a reliable onchain card drawing solution.

    The creator of Astrogator🐊 isn’t a fan of blind boxes; instead, it thinks unpacking cards right after purchase is more interesting.

    Spec

    When initializing this NFT contract, the creator will determine the total supply of it. And there will be an iterable function that is randomly picking a number from the remaining pool. The number must be in range and must not collide with any existing ones.

    Our top priority is accessibility/gas efficiency. Given that gas cost on Ethereum is damn high nowadays, we need an elegant algorithm to control gas expanse at an acceptable range.

    Achieving robust randomness isn’t the primary goal here. We assume there’s no strong financial incentive to cheat, so the RNG isn’t specified. Implementers can bring their own source of randomness that they think is good enough.

    Implementation

    Overview

    The implementation is pretty short and straightforward. Imagine there’s an array that contains all remaining(unsold) cards. When drawIndex() is called, it generates a (uniform) random seed to draw a card from the array, shortens the array, and returns the selected card.

    Algorithm

    Drawing X cards from a deck with the same X amount of cards is equal to shuffling the deck and dealing them sequentially. It’s not a surprise that our algorithm is similar to random shuffling, and the only difference is turning that classic algo into an interactive version.

    A typical random shuffle looks like this: for an array with N elements, you randomly pick a number i in (0,N), swap array[0] and array[i], then choose another number i in (1,N), swap array[1] and array[i], and so on. Eventually, you’ll get a mathematically random array in O(N) time.

    So, the concept of our random card dealing is the same. When a user mints a new card, the smart contract picks a number in the array as NFT index, then grabs a number from the tail to fill the vacancy, in order to keep the array continuous.

    Tweak

    Furthermore, as long as the space of the NFT index is known, we don’t need to declare/initialize an array(which is super gas-intensive). Instead, assume there’s such an array that the n-th element is n, we don’t actually initialize it (so it is an array only contains “0”) until the rule is broken.

    For the convenience of explanation, let’s call that mapping cache. If cache[i] is empty, it should be interpreted as i instead of 0. On the other hand, when a number is chosen and used, we’ll need to fill it up with another unused number. An intuitive method is to pick a number from the end of the array, since the length of the array is going to decrease by 1.

    By doing so, the gas cost in the worst-case scenario is bound to be constant.

    Performance and limitation

    Comparing with the normal ascending index NFT minting, our random NFT implementation requires two extra SSTORE and one extra SLOAD, which cost 12600 ~ 27600 (5000+20000+2600) excess gas per token minted.

    Theoretically, any instantly generated onchain random number is vulnerable. We can restrict contract interaction to mitigate risk. The mitigation is far from perfect, but it is the tradeoff that we have to accept.

    ping.eth

    Gas Efficient Card Drawing in Solidity was originally published in Taipei Ethereum Meetup on Medium, where people are continuing the conversation by highlighting and responding to this story.

    👏 歡迎轉載分享鼓掌

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