void findWords(char W[][], ArrayList<String> words, boolean visited[][], String s, int i, int j){
		if (i >= W.length || j >=W[0].length || i < 0 || j < 0 ){
			return;
		} else if (visited[i][j] == true){
			return;
		}
		
		visited[i][j]=true;
		s = s + W[i][j];
		if (isWord(s)){
			words.add(s);
		}
		
		findWords(W,words, visited, new String(s), i-1,j);
		findWords(W,words, visited, new String(s), i+1,j);
		findWords(W,words, visited, new String(s), i,j-1);
		findWords(W,words, visited, new String(s), i,j+1);
		visited[i][j]=false;
	}