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authorJack Sangdahl <[email protected]>2024-12-14 19:36:16 -0700
committerJack Sangdahl <[email protected]>2024-12-14 19:36:16 -0700
commit879781c5dd20ac3fffec6567a296c6643c7403be (patch)
tree45406fcbb4948dff4b85bd7e9ec839059d4d224a
parent6454a6e0421beab63ae3eacb584ef68b9dbac564 (diff)
downloadleetcode-879781c5dd20ac3fffec6567a296c6643c7403be.tar.gz
leetcode-879781c5dd20ac3fffec6567a296c6643c7403be.zip
1792. maximum average pass ratio
-rw-r--r--max_average_pass_ration.cpp57
-rw-r--r--max_average_pass_ration.py41
2 files changed, 98 insertions, 0 deletions
diff --git a/max_average_pass_ration.cpp b/max_average_pass_ration.cpp
new file mode 100644
index 0000000..3da2a9f
--- /dev/null
+++ b/max_average_pass_ration.cpp
@@ -0,0 +1,57 @@
+// 1792. Maximum Average Pass Ratio
+#include "leetcode.h"
+
+/*
+ * there is a school that has classes of student and each class will be having a
+ * final exam. you are given a 2d integer array 'classes', where 'classes[i] =
+ * [pass_i, total_i]'. you know beforehand that in the i'th class, there are
+ * 'total_i' total students, but only 'pass_i' number of students will pass the
+ * exam. you are also given an integer 'extraStudents'. there are another
+ * 'extraStudents' brilliant students that are guaranteed to pass the exam of
+ * any class they are assigned to. you want to assign each of the
+ * 'extraStudents' to a class in a way that maximises the average pass ration
+ * across all classes. return the maximum possible average pass ratio after
+ * assigning the 'extraStudents'. answers within '10^-5' of the actual answer
+ * will be accepted.
+ */
+
+struct cmp {
+ bool operator()(pair<int, int> a, pair<int, int> b) {
+ double aa =
+ (a.first + 1) / (double)(a.second + 1) - (a.first) / (double)a.second;
+ double bb =
+ (b.first + 1) / (double)(b.second + 1) - (b.first) / (double)b.second;
+ return aa < bb;
+ }
+};
+
+class Solution {
+public:
+ double maxAverageRatio(vector<vector<int>> &classes, int extraStudents) {
+ double acc = 0;
+ priority_queue<pair<int, int>, vector<pair<int, int>>, cmp> pq;
+ for (vector<int> i : classes)
+ pq.push(make_pair(i[0], i[1]));
+ while (extraStudents--) {
+ pair<int, int> curr = pq.top();
+ pq.pop();
+ curr.first++;
+ curr.second++;
+ pq.push(curr);
+ }
+ while (!pq.empty()) {
+ pair<int, int> curr = pq.top();
+ pq.pop();
+ acc += curr.first / (double)curr.second;
+ }
+ return acc / (double)classes.size();
+ }
+};
+
+int main() {
+ Solution obj;
+ vvd(int) c1 = {{1, 2}, {3, 5}, {2, 2}},
+ c2 = {{2, 4}, {3, 9}, {4, 5}, {2, 10}};
+ printf("%f\n", obj.maxAverageRatio(c1, 2)); // expect: 0.78333
+ printf("%f\n", obj.maxAverageRatio(c2, 4)); // expect: 0.53485
+}
diff --git a/max_average_pass_ration.py b/max_average_pass_ration.py
new file mode 100644
index 0000000..b528ea6
--- /dev/null
+++ b/max_average_pass_ration.py
@@ -0,0 +1,41 @@
+# 1792. Maximum Average Pass Ratio
+import heapq
+
+"""
+there is a school that has classes of student and each class will be having a
+final exam. you are given a 2d integer array 'classes', where 'classes[i] =
+[pass_i, total_i]'. you know beforehand that in the i'th class, there are
+'total_i' total students, but only 'pass_i' number of students will pass the
+exam. you are also given an integer 'extraStudents'. there are another
+'extraStudents' brilliant students that are guaranteed to pass the exam of
+any class they are assigned to. you want to assign each of the
+'extraStudents' to a class in a way that maximises the average pass ration
+across all classes. return the maximum possible average pass ratio after
+assigning the 'extraStudents'. answers within '10^-5' of the actual answer
+will be accepted.
+"""
+
+
+class Solution(object):
+ def maxAverageRatio(self, classes, extraStudents):
+ """
+ :type classes: List[List[int]]
+ :type extraStudents: int
+ :rtype: float
+ """
+ pq = [(a / b - (a + 1) / (b + 1), a, b) for a, b in classes]
+ heapq.heapify(pq)
+ while extraStudents:
+ v, a, b = heapq.heappop(pq)
+ a, b = a + 1, b + 1
+ heapq.heappush(pq, (-(a + 1) / (b + 1) + a / b, a, b))
+ extraStudents -= 1
+ return sum(a / b for v, a, b in pq) / len(pq)
+
+
+if __name__ == "__main__":
+ obj = Solution()
+ print(obj.maxAverageRatio(classes=[[1, 2], [3, 5], [2, 2]], extraStudents=2))
+ print(
+ obj.maxAverageRatio(classes=[[2, 4], [3, 9], [4, 5], [2, 10]], extraStudents=4)
+ )