Create moving_average_from_data_stream.py

yingl · web-flow · commit 8233448c8720 · 2018-06-18T22:11:15.000+08:00
diff --git a/moving_average_from_data_stream.py b/moving_average_from_data_stream.py
@@ -0,0 +1,23 @@
+class MovingAverage:
+    """
+    @param: size: An integer
+    """
+    def __init__(self, size):
+        # do intialization if necessary
+        self.size = size
+        self.queue = []
+        self.start = 0 # 考虑到用list模拟queue的效率，还是空间换时间吧。
+        self.total = float(0)
+
+    """
+    @param: val: An integer
+    @return:  
+    """
+    def next(self, val):
+        # write your code here
+        self.total += float(val)
+        self.queue.append(val)
+        if (len(self.queue) - self.start) > self.size:
+            self.total -= self.queue[self.start]
+            self.start += 1
+        return self.total / (len(self.queue) - self.start)
