Question

该程序的目的是生成由句点组成的二维网格阵列。用户将在网格上指定一个＆＃34; walker＆＃34;放置，标记为＆＃39; A＆＃39;。步行者将选择随机的基本方向进入，每次选择一个新的方向，并用字母表中的下一个字母标记它，直到它到达“Z”，或直到它超出边界。如果它到达已经存在的空间，它将检查其他三个方向并移动到它找到的下一个空白区域。

该程序在大多数情况下运行良好，但通常在运行的中点附近，它将向前跳过几个空格，或者留空间隙，或者看起来对角移动（它不应该。）< / p>

import java.lang.Math;
import java.util.Random;
import java.util.Scanner;

class DrunkWalker {
    private char[][] walkgrid = new char[10][10];
    private static int randNSEW;
    private static int randNSEWS;
    private int randomnum;
    private int startrow;
    private int startcol;
    private char alpha = 'A';
    private int nextrow;
    private int nextcol;

    public DrunkWalker(int r, int c) {
        startrow = r;
        startcol = c;
        nextrow = startrow;
        nextcol = startcol;

        for (int i = 0; i < 10; i ++) { 
//Fills walkgrid with periods.
            for (int j = 0; j < 10; j++)
                walkgrid[i][j] = '.';
        }
        walkgrid[r][c] = alpha++;
    }

    public static void getRand(){ 
//Generates number between 0-3
        int x100 = 0;
        double randomNum = 0.0;
        randomNum = Math.random();
        x100 = (int) (randomNum * 100);
        randNSEW = x100 % 4;
    }

    public static void getRandSecundus(){ 
//Generates number between 0-2 for corrections
        int x100 = 0;
        double randomNum = 0.0;
        randomNum = Math.random();
        x100 = (int) (randomNum * 100);
        randNSEWS = x100 % 3;
    }

    public int getNextRow(){
        return nextrow;
    }

    public int getNextCol(){
        return nextcol;
    }

    enum Mode {WALKING, CORRECTING};
    Mode mode =  Mode.WALKING;

    public boolean processing(){
    for(int i = 1; i < 26; i ++){ //Goes until it hits Z

        if (mode == Mode.WALKING) {
            getRand(); //Retrieves random direction
            if(randNSEW == 0){
                nextcol--; //west
            }
            if(randNSEW == 1){
                nextrow++; //south
            }
            if(randNSEW == 2){
                nextcol++; //east
            }
            if(randNSEW == 3){
                nextrow--; //north
            }
        }

//if walker goes out of bounds they are arrested.
        if(nextrow < 0 || nextrow >= 10 || nextcol < 0 || nextcol >= 10) {
            return false;
        }
        if(randNSEW == 0 && walkgrid[nextrow][nextcol] != '.'){
            //If walker headed west and lands somewhere it has already been
            i--; //Sets the counter back so it won't go further than Z.
            nextcol++; //Moves back in to place.
            mode = Mode.CORRECTING;
            getRandSecundus(); //Calls for secondary random number.
            if(randNSEWS == 0){
                nextrow++; //Check South.
            }
            if(randNSEWS == 1){
                nextcol++; //Check East.
            }
            if(randNSEWS == 2){
                nextrow--; //Check North.
            }
            continue;
        }
        if(randNSEW == 1 && walkgrid[nextrow][nextcol] != '.'){
            //If walker headed south and lands somewhere it has already been
            i--; //Sets the counter back so it won't go further than Z.
            nextrow--; //Moves back in to place.
            mode = Mode.CORRECTING;
            getRandSecundus(); //Calls for secondary random number.
            if(randNSEWS == 0){
                nextcol--; //Check West
            }
            if(randNSEWS == 1){
                nextcol++; //Check East
            }
            if(randNSEWS == 2){
                nextrow--; //Check North
            }
            continue;
        }
        if(randNSEW == 2 && walkgrid[nextrow][nextcol] != '.'){
            //If walker headed east and lands somewhere it has already been
            i--; //Sets the counter back so it won't go further than Z.
            nextcol--; //Moves back in to place.
            mode = Mode.CORRECTING;
            getRandSecundus(); //Calls for secondary random number.
            if(randNSEWS == 0){
                nextcol--; //Check West
            }
            if(randNSEWS == 1){
                nextrow++; //Check South
            }
            if(randNSEWS == 2){
                nextrow--; //Check North
            }
            continue;
        }
        if(randNSEW == 3 && walkgrid[nextrow][nextcol] != '.'){
            //If walker headed north and lands somewhere it has already been
            i--; //Sets the counter back so it won't go further than Z.
            nextrow++; //Moves back in to place.
            mode = Mode.CORRECTING;
            getRandSecundus();
            if(randNSEWS == 0){
                nextcol--; //Check West
            }
            if(randNSEWS == 1){
                nextrow++; //Check South
            }
            if(randNSEWS == 2){
                nextcol++; //Check East
            }
            continue;
        }

        mode = Mode.WALKING;
        walkgrid[nextrow][nextcol] = alpha++;
    }
    return true;
}




    public char[][] DisplayGrid() {
    for(int y = 0; y < 10; y++) {
        for(int x = 0; x < 10; x++) {
            System.out.print(walkgrid[x][y] + " ");
        }
        System.out.println();
    }
    return walkgrid;
}
}

public class WalkTester {

    public static void main(String[] args) {
        Scanner inpr = new Scanner(System.in);
        Scanner inpc = new Scanner(System.in);
        Scanner inpchoice = new Scanner(System.in);

        int r = 0;
        int c = 0;
        char choice = 'y';

        while(choice == 'y' || choice == 'Y') {
            System.out.println("Please enter x coordinate between 1 and 10.");
            r = inpr.nextInt();
            r = r - 1;

            System.out.println("Please enter y coordinate between 1 and 10");
            c = inpr.nextInt();
            c = c - 1;

            if(r < 0 || r > 9 || c < 0 || c > 9){
                System.out.println("Invalid Entry. Restart? y/n");
                choice = inpchoice.next().charAt(0);
                if(choice == 'y' || choice == 'Y'){
                    continue;
                }
                else if(choice == 'n' || choice == 'N'){
                    return;
                }
                else{
                    System.out.println("Invalid Entry. Restart? y/n");
                    choice = inpchoice.next().charAt(0);
                }
            }
            DrunkWalker drunkwalker = new DrunkWalker(r, c);
            boolean walkerSucceeded = drunkwalker.processing();
            drunkwalker.DisplayGrid();
            if(walkerSucceeded) {
            System.out.println("You made it home");
            } else {
            System.out.println("You were arrested");
            }

            System.out.println("Restart? y/n");
            choice = inpchoice.next().charAt(0);
            if(choice == 'y' || choice == 'Y'){
                continue;
            }
            else if(choice == 'n' || choice == 'N'){
                return;
            }
            else{
                System.out.println("Invalid Entry. Restart? y/n");
                choice = inpchoice.next().charAt(0);
            }
        }
    }
}

Answer 1

我发现了问题。在寻找新的旅行方向的过程中，您永远不会设置randNSEW以适应变化。您需要添加一行重新分配它以对应于与新randNSEWS值关联的方向。下面的工作代码：

if(randNSEW == 0 && walkgrid[nextrow][nextcol] != '.'){
    //If walker headed west and lands somewhere it has already been
    i--; //Sets the counter back so it won't go further than Z.
    nextcol++; //Moves back in to place.
    mode = Mode.CORRECTING;
    getRandSecundus(); //Calls for secondary random number.
    if(randNSEWS == 0){
        nextrow++; //Check South.
        randNSEW = 1; /////////////////////////// THIS LINE ADDED
    }
    if(randNSEWS == 1){
        nextcol++; //Check East.
        randNSEW = 2; /////////////////////////// THIS LINE ADDED
    }
    if(randNSEWS == 2){
        nextrow--; //Check North.
        randNSEW = 3; /////////////////////////// THIS LINE ADDED
    }
    continue;
}
if(randNSEW == 1 && walkgrid[nextrow][nextcol] != '.'){
    //If walker headed south and lands somewhere it has already been
    i--; //Sets the counter back so it won't go further than Z.
    nextrow--; //Moves back in to place.
    mode = Mode.CORRECTING;
    getRandSecundus(); //Calls for secondary random number.
    if(randNSEWS == 0){
        nextcol--; //Check West
        randNSEW = 0; /////////////////////////// THIS LINE ADDED
    }
    if(randNSEWS == 1){
        nextcol++; //Check East
        randNSEW = 2; /////////////////////////// THIS LINE ADDED
    }
    if(randNSEWS == 2){
        nextrow--; //Check North
        randNSEW = 3; /////////////////////////// THIS LINE ADDED
    }
    continue;
}
if(randNSEW == 2 && walkgrid[nextrow][nextcol] != '.'){
    //If walker headed east and lands somewhere it has already been
    i--; //Sets the counter back so it won't go further than Z.
    nextcol--; //Moves back in to place.
    mode = Mode.CORRECTING;
    getRandSecundus(); //Calls for secondary random number.
    if(randNSEWS == 0){
        nextcol--; //Check West
        randNSEW = 0; /////////////////////////// THIS LINE ADDED
    }
    if(randNSEWS == 1){
        nextrow++; //Check South
        randNSEW = 1; /////////////////////////// THIS LINE ADDED
    }
    if(randNSEWS == 2){
        nextrow--; //Check North
        randNSEW = 3; /////////////////////////// THIS LINE ADDED
    }
    continue;
}
if(randNSEW == 3 && walkgrid[nextrow][nextcol] != '.'){
    //If walker headed north and lands somewhere it has already been
    i--; //Sets the counter back so it won't go further than Z.
    nextrow++; //Moves back in to place.
    mode = Mode.CORRECTING;
    getRandSecundus();
    if(randNSEWS == 0){
        nextcol--; //Check West
        randNSEW = 0; /////////////////////////// THIS LINE ADDED
    }
    if(randNSEWS == 1){
        nextrow++; //Check South
        randNSEW = 1; /////////////////////////// THIS LINE ADDED
    }
    if(randNSEWS == 2){
        nextcol++; //Check East
        randNSEW = 2; /////////////////////////// THIS LINE ADDED
    }
    continue;
}

另外，疏忽：没有检查是否已经使用了所有四个相邻位置。如果DrunkWalker移动到已经访问过的位置所包围的位置，程序将挂起，因为它无法找到另一个方向。我建议写另一个if语句检查看看DrunkWalker是否被困，如果是的话就逮捕他。

在2d步行网格阵列中跳过空格

1 个答案: