--- /dev/null
+#include "sliding_tile_lib.h"
+#include "gflags/gflags.h"
+
+#include <iostream>
+#include <random>
+
+int main(int argc, char** argv) {
+ gflags::ParseCommandLineFlags(&argc, &argv, false);
+
+ Board goal{{1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,0}};
+ InvertedBoard invgoal = goal.invert();
+
+ Board rev{{0,15,14,13,12,11,10,9,8,7,6,5,4,3,2,1}};
+ std::cout << rev.distance(invgoal) << ": " << rev << std::endl;
+
+ std::random_device rd;
+ std::mt19937 rng(rd());
+
+ int max_distance = 0;
+ while (true) {
+ Board b{{0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}};
+ for (int i = 0; i < BOARD_SIZE; i++) {
+ std::uniform_int_distribution<> get_random_number(0, i);
+ std::swap(b.board[i], b.board[get_random_number(rng)]);
+ }
+ int dist = b.distance(invgoal);
+ if (dist > max_distance) {
+ max_distance = dist;
+ }
+ if (dist > max_distance - 2) {
+ std::cout << dist << ": " << b << std::endl;
+ }
+ }
+}