41 lines
965 B
C++
41 lines
965 B
C++
#include <queue>
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#include <utility>
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#include <numeric>
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#include <execution>
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class Solution {
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public:
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static double maxAverageRatio(std::vector<std::vector<int>>& c, int ex) {
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int n = c.size();
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double ans = std::transform_reduce(
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std::execution::par,
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c.begin(),
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c.end(),
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0.0,
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std::plus{},
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[](const std::vector<int>& x) {
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return double(x[0]) / double(x[1]);
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}
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);
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std::priority_queue<std::pair<double, int>> incr;
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for (int i = 0; i < n; ++i)
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incr.emplace(double(c[i][0] + 1) / double(c[i][1] + 1) - double(c[i][0]) / double(c[i][1]), i);
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while (ex--) {
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const auto [delta, i] = incr.top();
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incr.pop();
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ans += delta;
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++c[i][0], ++c[i][1];
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incr.emplace(double(c[i][0] + 1) / double(c[i][1] + 1) - double(c[i][0]) / double(c[i][1]), i);
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}
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return ans / n;
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}
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};
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int main() {
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std::vector<std::vector<int>> c {
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{2,4},{3,9},{4,5},{2,10}
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};
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std::printf("%.6f\n", Solution::maxAverageRatio(c, 4));
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return 0;
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}
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