inclass code

src/SalamanderSearch.java

@@ -43,6 +43,72 @@ public static void main(String[] args) {
      * @return whether the salamander can reach the food
      */
     public static boolean canReach(char[][] enclosure) {
+        int[] start = salamanderLocation(enclosure);
+        boolean[][] visited = new boolean[enclosure.length][enclosure[0].length];
+        return canReach(enclosure, start, visited);
+    }
+
+    public static boolean canReach(char[][] enclosure, int[]current, boolean[][] visited) {
+        int curR = current[0];
+        int curC = current[1];
+
+        if(visited[curR][curC]) return false;
+        if(enclosure[curR][curC] == 'f') return true;
+
+        visited[curR][curC] = true;
+
+        List<int[]> moves = possibleMoves(enclosure, current);
+        for(int[] move : moves) {
+            if(canReach(enclosure, move, visited)) return true;
+        }
         return false;
     }
-}
+
+    public static List<int[]> possibleMoves(char[][] enclosure, int[] current) {
+        int curR = current[0];
+        int curC = current[1];
+
+        List<int[]> moves = new ArrayList<>();
+
+        // UP 
+        int newR = curR - 1;
+        int newC = curC;
+        if(newR >= 0 && enclosure[newR][newC] != 'W') {
+            moves.add(new int[]{newR, newC});
+        }
+
+        //DOWN
+        newR = curR + 1;
+        newC = curC;
+        if(newR < enclosure.length && enclosure[newR][newC] != 'W') {
+            moves.add(new int[]{newR, newC});
+        }
+
+        //LEFT
+        newR = curR;
+        newC = curC - 1;
+        if(newC >= 0 && enclosure[newR][newC] != 'W') {
+            moves.add(new int[]{newR, newC});
+        }
+
+        //RIGHT
+        newR = curR;
+        newC = curC + 1;
+        if(newC < enclosure[0].length && enclosure[newR][newC] != 'W') {
+            moves.add(new int[]{newR, newC});
+        }
+
+        return moves;
+    }
+
+    public static int[] salamanderLocation(char[][] enclosure) {
+        for(int r = 0; r < enclosure.length; r++) {
+            for(int c = 0; c < enclosure[0].length; c++) {
+                if(enclosure[r][c] == 's') {
+                    return new int[]{r, c};
+                }
+            }
+        }
+        throw new IllegalArgumentException("No salamander present");
+    }
+}