Matrix

.vscode/settings.json

@@ -0,0 +1,3 @@
+{
+    "java.debug.settings.onBuildFailureProceed": true
+}

src/SalamanderSearch.java

@@ -44,6 +44,88 @@ public static void main(String[] args) {
      * @throws IllegalArgumentException if the enclosure does not contain a salamander
      */
     public static boolean canReach(char[][] enclosure) {
+        int[] start = salamanderLocation(enclosure);
+        boolean[][] visited = new boolean[enclosure.length][enclosure[0].length];
+        return canReach(enclosure, start, visited);
+    }
+
+    //questions:
+    //
+    //
+    public static boolean canReach(char[][] enclosure, int[] current, boolean[][] visited)
+    {
+        int curR = current[0];
+        int curC = current[1];
+        if(enclosure[curR][curC] == 'f') return true;    //if the food is found
+
+        if(visited[curR][curC]) return false;    //if we've already seen that location 
+
+        visited[curR][curC] = true;
+
+        List<int[]> neighbors = possibleMoves(enclosure, current);    //getting the possible places you can move using recursion
+        for(int[] neighbor : neighbors)
+        {
+            if(canReach(enclosure, neighbor, visited)) return true;     //??
+        }
         return false;
     }
+
+    public static List<int[]> possibleMoves(char[][] enclosure, int[] current)
+    {
+        List<int[]> moves = new ArrayList<>();
+
+        int curR = current[0];
+        int curC = current[1];
+
+        //UP
+        int newRow = curR-1;
+        int newCol = curC;
+
+        if(newRow >= 0 && enclosure[newRow][newCol] != 'W')
+        {
+            moves.add(new int[]{newRow,newCol});
+        }
+        //DOWN
+        newRow = curR+1;
+        newCol = curC;
+
+        if(newRow < enclosure.length && enclosure[newRow][newCol] != 'W')
+        {
+            moves.add(new int[]{newRow,newCol});
+        }
+        //LEFT
+        newRow = curR;
+        newCol = curC-1;
+        if(newCol >= 0 && enclosure[newRow][newCol] != 'W')
+        {
+            moves.add(new int[]{newRow,newCol});
+        }
+
+        //RIGHT
+        newRow = curR;
+        newCol = curC+1;
+        if(newCol < enclosure[newRow].length && enclosure[newRow][newCol] != 'W')
+        {
+            moves.add(new int[]{newRow,newCol});
+        }
+        return moves;
+    }
+    //O(n*m):
+    //n = # of cols 
+    //m = # of rows
+    public static int[] salamanderLocation(char[][] enclosure)
+    {
+        for(int row = 0; row < enclosure.length; row++)
+        {
+            for(int col = 0; col < enclosure[0].length; col++)
+            {
+                if(enclosure[row][col] == 's')
+                {
+                    int[] location = new int[] {row,col};
+                    return location;
+                }
+            }
+        }
+        throw new IllegalArgumentException("No salamander present");
+    }
 }