Dice simulator

Uebung-02/dice.cpp

@@ -0,0 +1,60 @@
+#include <pybind11/pybind11.h>
+#include <pybind11/stl.h>
+#include <random>
+#include <map>
+#include <set>
+#include <string>
+#include <vector>
+
+class Dice {
+    std::vector<std::string> sides;
+    std::vector<double> probs;
+    std::mt19937 gen;
+    std::discrete_distribution<> dist;
+
+public:
+    size_t accepted = 0;
+    size_t rejected = 0;
+
+    Dice(const std::vector<std::string>& sides, const std::vector<double>& probs)
+        : sides(sides), probs(probs), gen(std::random_device{}()), dist(probs.begin(), probs.end()) {}
+
+    std::string fair_dice() {
+        while (true) {
+            std::vector<std::string> res;
+            for (size_t i = 0; i < sides.size(); ++i)
+                res.push_back(sides[dist(gen)]);
+            std::set<std::string> uniq(res.begin(), res.end());
+            if (uniq.size() == res.size()) {
+                ++accepted;
+                return res[0];
+            }
+            ++rejected;
+        }
+    }
+
+    std::map<std::string,int> throw_dice(int n) {
+        std::map<std::string,int> res;
+        for (auto& s : sides) res[s] = 0;
+        for (int i = 0; i < n; ++i)
+            res[fair_dice()]++;
+        return res;
+    }
+
+    std::pair<size_t,size_t> stats() const { return {accepted, rejected}; }
+
+    void reset_stats() { accepted = rejected = 0; }
+};
+
+namespace py = pybind11;
+
+PYBIND11_MODULE(dice, m) {
+    py::class_<Dice>(m, "Dice")
+        .def(py::init<const std::vector<std::string>&, const std::vector<double>&>())
+        .def("fair_dice", &Dice::fair_dice)
+        .def("throw_dice", &Dice::throw_dice)
+        .def("stats", &Dice::stats)
+        .def("reset_stats", &Dice::reset_stats)
+        .def_readwrite("accepted", &Dice::accepted)
+        .def_readwrite("rejected", &Dice::rejected);
+}