Java-Boggle / Word矩陣求解器路徑問題

Question

我正在制作一個應用程序，它將查找可以在4x4網格（Boggle）上使用相鄰圖塊創建的所有單詞。 我到了可以輸入字母字符串的地方，該算法將在最佳時間內找到所有可用的單詞。 但是，我不僅要知道有效的單詞，還要知道它們在板上的位置。

這是主要的游戲類。 該算法以一個字母遞歸開始，然后檢查是否存在以該字母加上其鄰居開頭的單詞。 如果不存在任何單詞，則路徑將被阻塞，並且算法將移至下一個字母。 如果存在帶有該前綴的單詞，請對該鄰居執行相同的操作。

import java.io.IOException;
import java.util.ArrayList;

public class Game {
private final int boardSize = 4;
private BoardSquare[][] squares;
private ArrayList<String> validWords;
private static WordTree trie;
private static int counter = 0;
private DevRunner runner;

public Game(String letters) throws IOException{
    validWords = new ArrayList<String>();
    runner = new DevRunner();
    trie = new WordTree();
    squares = new BoardSquare[boardSize][boardSize];
    for (int y=0; y<boardSize; y++){
        for (int x=0; x<boardSize; x++){
            squares[x][y] = new BoardSquare(letters.charAt(y*boardSize + x), y*boardSize + x);
        }
    }
    for (int y=0; y<boardSize; y++){
        for (int x=0; x<boardSize; x++){
            for (int a=-1; a<2; a++){
                for (int b=-1; b<2; b++){
                    if (a == 0 && b == 0) continue;
                    if (x+b < 0 || y+a < 0) continue;
                    if (x+b > boardSize-1 || y+a > boardSize-1) continue;
                    squares[x][y].addNeighbor(squares[x+b][y+a]);
                }
            }
        }
    }
    getPossibleCombinations();
    System.out.println(counter + " words found.");
}

public void getPossibleCombinations(){
    for (int y=0; y<boardSize; y++){
        for (int x=0; x<boardSize; x++){
            doNeigh(squares[x][y], "", new ArrayList<Integer>());
        }
    }
}

public void doNeigh(BoardSquare square, String path, ArrayList<Integer> locations) {
    square.setIsActive(true);
    path += square.getData();
    locations.add(square.getPosition());
    if (trie.has(path) != 0){
        for (BoardSquare neighbor : square.getNeighbors()){
            if (!neighbor.getIsActive()){
                doNeigh(neighbor, path, locations);
                };
            }
        }
    if (trie.has(path) == 1 && !validWords.contains(path)){
        System.out.print(path + " is a word! (");
        validWords.add(path);
        for (int i : locations){
            System.out.print(i + " -> ");
        }
        System.out.print("\n");
        sendWord(path);
        counter++;
    }
    square.setIsActive(false);
}

public void sendWord(String s){

}

public static void main(String[] args){
    try {
        long t1 = System.currentTimeMillis();
        Game g = new Game("SIOZTRTEBAINERLA");
        long t2 = System.currentTimeMillis();
        System.out.println("The algorithm took " + Long.toString(t2-t1) + " milliseconds to complete.");
    } catch (IOException e) {
        e.printStackTrace();
    }
}
}

實際輸出：

SITAR is a word! (0 -> 1 -> 2 -> 4 -> 5 -> 8 -> 9 -> 5 -> 2 -> 6 -> 8 -> 10 -> 6 -> 7 -> 11 -> 13 -> 14 -> 15 -> 
SIT is a word! (0 -> 1 -> 2 -> 4 -> 5 -> 8 -> 9 -> 5 -> 2 -> 6 -> 8 -> 10 -> 6 -> 7 -> 11 -> 13 -> 14 -> 15 -> 6 -> 8 -> 10 -> 12 -> 13 -> 8 -> 10 -> 5 -> 6 -> 7 -> 11 -> 14 -> 15 -> 12 -> 14 -> 14 -> 
SIR is a word! (0 -> 1 -> 2 -> 4 -> 5 -> 8 -> 9 -> 5 -> 2 -> 6 -> 8 -> 10 -> 6 -> 7 -> 11 -> 13 -> 14 -> 15 -> 6 -> 8 -> 10 -> 12 -> 13 -> 8 -> 10 -> 5 -> 6 -> 7 -> 11 -> 14 -> 15 -> 12 -> 14 -> 14 -> 5 -> 2 -> 3 -> 6 -> 7 -> 4 -> 6 -> 8 -> 9 -> 10 -> 6 -> 7 -> 9 -> 11 -> 6 -> 7 -> 14 -> 15 -> 13 -> 14 -> 15 -> 

預期產量：

SITAR is a word! (0 -> 1 -> 4 -> 9 -> 5 ->
SIT is a word! (0 -> 1 -> 4 ->
SIR is a word! (0 -> 1 -> 5 ->
...

我不明白為什么我可以使用doNeigh（）方法並通過遞歸來構建String path ，但是當我嘗試以相同方式構建正方形位置的String path時，它會包含一堆不會彌補這個詞。

任何幫助表示贊賞，謝謝。

Answer 1

您必須從doNeigh()末尾的locations刪除最后一個元素。 否則，此路徑將無限期增長。