Create basic, rule-based solver

solve.h

@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2022 Camden Dixie O'Brien
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program.  If not, see
+ * <https://www.gnu.org/licenses/>.
+ */
+
+#ifndef SOLVE_H
+#define SOLVE_H
+
+#include "sud.h"
+
+/**
+ * Attempt to solve the given sudoku. Returns when no rules match for
+ * an entire pass over the puzzle.
+ */
+bool solve(struct sudoku *sud);
+
+#endif