completed in class

src/Search.java

@@ -1,3 +1,5 @@
+import java.util.*;
+
 public class Search {
      /**
      * Finds the location of the nearest reachable cheese from the rat's position.
@@ -29,6 +31,102 @@ public class Search {
      * @throws HungryRatException if there is no reachable cheese
      */
     public static int[] nearestCheese(char[][] maze) throws EscapedRatException, CrowdedMazeException, HungryRatException {
-        return null;
+        boolean[][] visited = new boolean[maze.length][maze[0].length];
+        int[] start = ratLocation(maze);
+
+        //queue = []
+        //queue.add(start);
+        //while(queue != empty)
+        //{current = queue.pop()
+        //if visited continue
+        //mark visited
+        //if current == cheese return current
+        //add all neighbors to queue
+        //}
+        //throw hungry;
+
+        Queue<int[]> queue = new LinkedList<>();
+        queue.add(start);
+        while(!queue.isEmpty())
+        {
+            int[] current = queue.poll();
+            if(visited[current[0]][current[1]])
+            {
+                continue;
+            }
+
+            visited[current[0]][current[1]] = true;
+
+            if(maze[current[0]][current[1]] == 'c')
+            {
+                return current;
+            }
+
+            List<int[]> neighbors = getNeighbors(maze, current);
+            queue.addAll(neighbors);
+        }
+
+        throw new HungryRatException();
+    }
+
+    public static List<int[]> getNeighbors(char[][] maze, int[] current)
+    {
+        int curC = current[0];
+        int curR = current[1];
+
+        int[][] directions = {
+            {-1,0}, //up
+            {1,0}, //down
+            {0,-1}, //left
+            {0,1} //right
+        };
+
+        List<int[]> possibleMoves = new ArrayList<>();
+
+        for(int[] d : directions)
+        {
+            int changeR = d[0];
+            int changeC = d[1];
+
+            int newR = curR + changeR;
+            int newC = curC + changeC;
+
+            if(newR >= 0 && newR < maze.length && 
+               newC >= 0 && newC < maze[newR].length 
+               && maze[newR][newC] != 'w')
+            {
+                //valid move
+                int[] validMove = {newR, newC};
+                possibleMoves.add(validMove);
+            }
+        }
+        return possibleMoves;
+    }
+
+    public static int[] ratLocation(char[][] maze) throws EscapedRatException, CrowdedMazeException {
+        int[] location = null;
+
+        //searching
+        for(int r = 0; r < maze.length; r++)
+        {
+            for(int c = 0; c < maze[r].length; c++)
+            {
+                if(maze[r][c] == 'R')
+                {
+                    if(location != null)
+                    {
+                        throw new CrowdedMazeException();
+                    }                    
+                    location = new int[] {r, c};
+                }
+            }
+        }
+        if(location == null)
+        {
+            //404 rat not found
+            throw new EscapedRatException();
+        }
+
+        return location;
     }
 }