Algo code (considering phantom blocks)

ExplorationHex.txt

@@ -0,0 +1 @@
+ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff

ObstacleHex.txt

@@ -0,0 +1 @@
+0400000800000201c00002000400080010202040408000000000000003f80000000000000200

src/algorithms/Direction.java

@@ -0,0 +1,9 @@
+package algorithms;
+
+public enum Direction
+{
+    RIGHT,
+    LEFT,
+    UP,
+    DOWN;
+}

src/algorithms/ExplorationTypes.java

@@ -0,0 +1,30 @@
+package algorithms;
+
+public enum ExplorationTypes{
+	EMPTY(0), OBSTACLE(1),UNEXPLORED_EMPTY(2),UNEXPLORED_OBSTACLE(3);
+
+	int type_val = 2;
+    public int getValue() 
+    { 
+        return this.type_val; 
+    } 
+
+    public static int toInt(String a) {
+        switch(a) {
+            case "EMPTY": 
+                return 0;
+            case "OBSTACLE": 
+                return 1;
+            case "UNEXPLORED_EMPTY": 
+                return 2;
+            case "UNEXPLORED_OBSTACLE": 
+                return 3;
+        }
+        return -1;
+    };
+    // enum constructor - cannot be public or protected 
+    private ExplorationTypes(int type_val) 
+    { 
+        this.type_val = type_val; 
+    } 
+};