add: 0943

cpp/more/0943.cpp

@@ -0,0 +1,110 @@
+#include <iostream>
+#include <numeric>
+#include <vector>
+#include <string>
+#include <random>
+#include <ctime>
+#include <algorithm>
+#include <cstdio>
+
+// INCOMPLETE
+class Solution {
+private:
+	static int calc_dist(const std::string&, const std::string&);
+
+	static void get_next(std::mt19937&, std::vector<int>&, int = 1);
+
+	static const inline int ITER_COUNT = 2200000;
+public:
+	static std::string shortestSuperstring(const std::vector<std::string>&);
+};
+
+std::string Solution::shortestSuperstring(const std::vector<std::string>& w) {
+	const int n = w.size();
+	int dist[12][12]{}, MAX_DIST = 1;
+	for (int i = 0; i < n; ++i) {
+		for (int j = i + 1; j < n; ++j) {
+			dist[i][j] = calc_dist(w[i], w[j]);
+			dist[j][i] = calc_dist(w[j], w[i]);
+			MAX_DIST = std::max(MAX_DIST, std::max(dist[i][j], dist[j][i]));
+		}
+	}
+	auto energy = [&](const std::vector<int>& v) {
+		int ret = 0;
+		for (int i = 1; i < v.size(); ++i)
+			ret += dist[v[i - 1]][v[i]];
+		return -ret;
+	};
+	auto print_state = [](const char* prompt, const std::vector<int>& v) {
+		std::printf("%s: ", prompt);
+		for (int i : v)
+			std::printf("%2d ", i);
+		std::printf("\n");
+	};
+	auto seed = std::time(nullptr);
+	std::cout << "Seed = " << seed << "\n";
+	std::mt19937 r(seed);
+	std::vector<int> state(n), next_state;
+	std::iota(state.begin(), state.end(), 0);
+	int current_energy = energy(state);
+	for (int i = 0; i < ITER_COUNT; ++i) {
+		// std::printf("ITERATION # %d\n", i);
+		// Temperature is defined as (ITER_COUNT - i);
+		next_state = state;
+		get_next(r, next_state);
+		// print_state("Current state", state);
+		// print_state("Next state", next_state);
+		int next_energy = energy(next_state);
+		if (next_energy <= current_energy) {
+			// std::printf("Next E = %d < %d (Current E), accepting new state.\n", next_energy, current_energy);
+			state = next_state;
+			current_energy = next_energy;
+		} else if (double x = (double(r()) / r.max()), dte = double(current_energy - next_energy) / (double(ITER_COUNT - i) / ITER_COUNT * MAX_DIST), dt = std::exp(dte); x < dt) {
+			// std::printf("Next state worse (%d >= %d), rand = %.5f and exp(dE / T) = %.5f, accept anyway.\n", next_energy, current_energy, x, dt);
+			state = next_state;
+			current_energy = next_energy;
+		} else {
+			// std::printf("Next state worse (%d >= %d), rand = %.5f and exp(dE / T) = %.5f, rejected.\n", next_energy, current_energy, x, dt);
+		}
+		// std::printf("------------------------------------------------\n");
+	}
+	print_state("Final state", state);
+	std::printf("ENERGY = %d\n", energy(state));
+	std::string ret = w[state[0]];
+	for (int i = 1; i < n; ++i)
+		ret += w[state[i]].substr(dist[state[i - 1]][state[i]]);
+	return ret;
+}
+
+int Solution::calc_dist(const std::string& s, const std::string& t) {
+	const int m = s.size(), n = t.size();
+	int k = std::min(m, n), r = 0;
+	for (int i = 1; i <= k; ++i) {
+		int p = m - i, q = 0, ok = 1;
+		for (; p < m; ++p, ++q) {
+			if (s[p] != t[q]) {
+				ok = 0;
+				break;
+			}
+		}
+		r = ok ? i : r;
+	}
+	return r;
+}
+
+void Solution::get_next(std::mt19937& r, std::vector<int>& v, int c) {
+	int i, j;
+	while (c--) {
+		i = double(r()) / r.max() * v.size();
+		j = double(r()) / r.max() * v.size();
+		std::swap(v[i], v[j]);
+	}
+}
+
+int main() {
+	auto r = Solution::shortestSuperstring({"cgjufdqhfw","bsrchpiau","hfwbsrchpi","sezsorql","srchpiaues","rqlmc"});
+	Solution::shortestSuperstring({"wmiy","yarn","rnnwc","arnnw","wcj"});
+	Solution::shortestSuperstring({"jap","zebr","ebrxx","apz"});
+	std::printf("%s\n", r.c_str());
+	return 0;
+}

cpp/more/CMakeLists.txt

@@ -3,4 +3,4 @@ PROJECT(more)
 
 SET(CMAKE_CXX_STANDARD 23)
 
-ADD_EXECUTABLE(more 0001.cpp)
+ADD_EXECUTABLE(more 0943.cpp)