From a1965365b68ea99c59d0b7357397548e0bd7f57a Mon Sep 17 00:00:00 2001
From: Joshua Moerman <lakseru@gmail.com>
Date: Thu, 30 Jul 2015 14:02:17 +0200
Subject: [PATCH] Adds a simple random machine generator

---
 src/generator.cpp | 90 +++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 90 insertions(+)
 create mode 100644 src/generator.cpp

diff --git a/src/generator.cpp b/src/generator.cpp
new file mode 100644
index 0000000..5153a53
--- /dev/null
+++ b/src/generator.cpp
@@ -0,0 +1,90 @@
+#include <mealy.hpp>
+#include <reachability.hpp>
+#include <splitting_tree.hpp>
+
+#include <iostream>
+#include <random>
+#include <fstream>
+
+using namespace std;
+
+static size_t number_of_leaves(splitting_tree const & root) {
+	if (root.children.empty()) return 1;
+
+	return accumulate(root.children.begin(), root.children.end(), 0ul,
+	                  [](auto const & l, auto const & r) { return l + number_of_leaves(r); });
+}
+
+static mealy generate_random_machine(size_t N, size_t P, size_t Q, mt19937 & gen) {
+	mealy m;
+
+	m.graph_size = N;
+	m.input_size = P;
+	m.output_size = Q;
+
+	m.graph.assign(m.graph_size, vector<mealy::edge>(m.input_size));
+
+	uniform_int_distribution<output> o_dist(0, m.output_size - 1);
+	uniform_int_distribution<state> s_dist(0, m.graph_size - 1);
+
+	for (state s = 0; s < m.graph_size; ++s) {
+		for (input i = 0; i < m.input_size; ++i) {
+			m.graph[s][i] = {s_dist(gen), o_dist(gen)};
+		}
+	}
+
+	return m;
+}
+
+static void print_machine(mealy const & m, size_t count) {
+	ofstream file("machine_" + to_string(m.graph_size) + "_" + to_string(m.input_size) + "_" + to_string(m.output_size) + "_" + to_string(count) + ".txt");
+	for (state s = 0; s < m.graph_size; ++s) {
+		for (input i = 0; i < m.input_size; ++i) {
+			auto e = m.graph[s][i];
+			file << s << " -- " << i << " / " << e.out << " -> " << e.to << endl;
+		}
+	}
+}
+
+int main(int argc, char * argv[]) {
+	if (argc != 5 && argc != 6) {
+		cerr << "usage: generator <N> <P> <Q> <number of machines> [<seed>]" << endl;
+		return 1;
+	}
+
+	const auto N = stoul(argv[1]);
+	const auto P = stoul(argv[2]);
+	const auto Q = stoul(argv[3]);
+	const auto number_of_machines = stoul(argv[4]);
+
+	auto gen = [&] {
+		if (argc == 6) {
+			auto seed = stoul(argv[5]);
+			return mt19937(seed);
+		}
+		random_device rd;
+		return mt19937(rd());
+	}();
+
+	size_t count = 0;
+	size_t connected = 0;
+	size_t minimal = 0;
+
+	while (true) {
+		auto const m = generate_random_machine(N, P, Q, gen);
+		auto const m2 = reachable_submachine(m, 0);
+		auto const tree = create_splitting_tree(m2, min_hopcroft_style, 0).root;
+
+		count++;
+		if (m.graph_size == m2.graph_size) connected++;
+		if (number_of_leaves(tree) == m.graph_size) minimal++;
+
+		if (number_of_leaves(tree) == m.graph_size) {
+			print_machine(m2, minimal);
+		}
+
+		if (minimal >= number_of_machines) break;
+	}
+
+	clog << minimal << " / " << connected << " / " << count << endl;
+}