Create maximum-average-pass-ratio.py

Author: kamyu104

Python/maximum-average-pass-ratio.py

@@ -0,0 +1,24 @@
+# Time:  O(n + mlogn)
+# Space: O(n)
+
+import heapq
+
+
+class Solution(object):
+    def maxAverageRatio(self, classes, extraStudents):
+        """
+        :type classes: List[List[int]]
+        :type extraStudents: int
+        :rtype: float
+        """
+        def profit(a, b):
+            return float(a+1)/(b+1)-float(a)/b
+
+        max_heap = [(-profit(a, b), a, b) for a, b in classes]
+        heapq.heapify(max_heap)
+        while extraStudents:
+            v, a, b = heapq.heappop(max_heap)
+            a, b = a+1, b+1
+            heapq.heappush(max_heap, (-profit(a, b), a, b))
+            extraStudents -= 1
+        return sum(float(a)/b for v, a, b in max_heap)/len(classes)