隨機數算法

Question

我必須實現抽獎算法。問題是我希望一些參與者有更多的機會，因爲他們有更多的積分。我怎樣才能做到這一點？ 我希望簡單地把它們放在抽獎中多次，但似乎並不合法。 你知道有哪些算法可以做到嗎？

謝謝

Answer 1

爲什麼這不是「合法的」。如果你將你的機會數量基於若干分數，則根據他的分數將該人員添加到抽獎中X次。那個人的機會增加了。

我會以這種方式解決它。

Answer 2

僞算法：

winnerTicket <- a random number between zero and sum ticket count - 1 
currentTicket <- 0 
For each participant in participants ordered by id 
    If winnerTicket - currentTicket > participant.ticketCount 
     currentTicket += participant.ticketCount 
    Else 
     return participant 

Answer 3

你有一個映射：participant => number of chances。在許多編程語言可以聲明映射或字典是這樣的：

{"player1": 2, "player2": 5, ... many more like these} 

這樣你就可以遍歷這樣的：

accumulatedMap = {} #an empty map 
total = 0 
for each pair of key:count in the mapping: 
    total = total + count 
    accumulatedMap[key] = total 

#now, get random and calculate 
element = random between 1 and total, inclusive. 
for each pair of key:accumulated in the mapping: 
    if element <= accumulated: 
     return key 
#at this point, in the worst case the last key was returned. 

該代碼僅僅是一個例子。請記住，迭代時映射並不總是保持插入順序。