[Swift]LeetCode346.从数据流中移动平均值$MovingAveragefromDataStream

OStack程序员社区-中国程序员成长平台 › 门户 › 编程› 移动开发›Swift 教程

原作者: [db:作者] 来自: [db:来源] 收藏邀请

★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★
➤微信公众号：山青咏芝（shanqingyongzhi）
➤博客园地址：山青咏芝（https://www.cnblogs.com/strengthen/）
➤GitHub地址：https://github.com/strengthen/LeetCode
➤原文地址： https://www.cnblogs.com/strengthen/p/10740116.html
➤如果链接不是山青咏芝的博客园地址，则可能是爬取作者的文章。
➤原文已修改更新！强烈建议点击原文地址阅读！支持作者！支持原创！
★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★★

热烈欢迎，请直接点击！！！

进入博主App Store主页，下载使用各个作品！！！

注：博主将坚持每月上线一个新app！！！

Given a stream of integers and a window size, calculate the moving average of all integers in the sliding window.

For example,
MovingAverage m = new MovingAverage(3);
m.next(1) = 1
m.next(10) = (1 + 10) / 2
m.next(3) = (1 + 10 + 3) / 3
m.next(5) = (10 + 3 + 5) / 3

给定整数流和窗口大小，计算滑动窗口中所有整数的移动平均值。

例如，

MovingAverage m = new MovingAverage(3);

m.next(1) = 1
m.next(10) = (1 + 10) / 2
m.next(3) = (1 + 10 + 3) / 3
m.next(5) = (10 + 3 + 5) / 3

Solution:

 1 class MovingAverage {
 2     var q:[Int] = [Int]()
 3     var size:Int = 0
 4     var sum:Double = 0
 5     init(_ size:Int)
 6     {
 7         self.size = size
 8         sum = 0        
 9     }
10     
11     func next(_ val:Int) -> Double
12     {
13         if q.count >= size
14         {
15             let num:Double = Double(q.removeFirst())
16             sum -= num
17         }
18         q.append(val)
19         sum += Double(val)
20         return sum / Double(q.count)
21     }
22 }

点击：Playground测试

 1 var m:MovingAverage = MovingAverage(3)
 2 //m.next(1) = 1
 3 print(m.next(1))
 4 //Print 1.0
 5 
 6 //m.next(10) = (1 + 10) / 2
 7 print(m.next(10))
 8 //Print 5.5
 9 
10 //m.next(3) = (1 + 10 + 3) / 3
11 print(m.next(3))
12 //Print 4.666666666666667
13 
14 //m.next(5) = (10 + 3 + 5) / 3
15 print(m.next(5))
16 //Print 6.0