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我为创建 ascii 迷宫而编写的算法有问题。该代码使用递归回溯，伪代码本质上是：

1. Make the initial cell the current cell and mark it as visited
2. While there are unvisited cells
    1. If the current cell has any neighbours which have not been visited
        1. Choose randomly one of the unvisited neighbours
        2. Push the chosen cell to the stack
        3. Remove the wall between the current cell and the chosen cell
        4. Make the chosen cell the current cell and mark it as visited
    2. Else
        1. Pop a cell from the stack
        2.Make it the current cell

我遇到的问题是代码陷入了添加到堆栈然后弹出堆栈的循环中。该代码目前在第 19 行使用一个用于 linux 的系统命令，如果有人需要为 Windows 机器更改它

#include<iostream>
#include<cstdlib>
#include<stack>
#include<ctime>

#define NORTH   0
#define SOUTH   1
#define EAST    2
#define WEST    3
#define SIZEX   20
#define SIZEY   20

using namespace std;

int nGood = 0;
int locX = 1, locY = 1;

void printGrid(char grid[SIZEY][SIZEX]){
system("clear");
for (int i = 0; i < SIZEY; i++){
    for(int j = 0; j < SIZEX; j++){
        cout << grid[i][j];
    }
    cout << endl;
}
}

int moveEW(int direction, int x){
    if (direction == EAST)
            return x + 1;
    else if (direction == WEST)
            return x - 1;
    else
            return x;
}

int moveNS(int direction, int y){
    if (direction == NORTH)
            return y - 1;
    else if (direction == SOUTH)
            return y + 1;
    else
            return y;
}

 bool isGood(int x, int y, int direction, char grid[SIZEY][SIZEX]){
x = moveEW(direction,x);
y = moveNS(direction,y);

if (grid[x][y] == '.' || x >= (SIZEX - 1) || x <= 0 || y <= 0 || y >= (SIZEY - 1)){
    return false;
}

// check cardinal directions
if (direction == NORTH){
    if (grid[y][x-1] != '.' &&  grid[y-1][x] != '.' && grid[y][x+1] != '.' &&  grid[y-1][x-1] != '.' && grid[y-1][x+1] != '.'){
        return true;
    }
}
if (direction == SOUTH){
            if (grid[y][x-1] != '.' &&  grid[y+1][x] != '.' && grid[y][x+1] != '.' && grid[y+1][x-1] != '.' && grid[y+1][x+1] != '.'){
                    return true;
            }
    }
if (direction == EAST){
            if (grid[y][x+1] != '.' &&  grid[y-1][x] != '.' && grid[y+1][x] != '.' && grid[y-1][x+1] != '.' && grid[y+1][x+1] != '.'){
                    return true;
            }
    }
if (direction == WEST){
            if (grid[y][x-1] != '.' &&  grid[y-1][x] != '.' && grid[y+1][x] != '.' && grid[y-1][x-1] != '.' && grid[y+1][x-1] != '.'){
                    return true;
            }
    }
return false;
}

main(){
char grid[SIZEY][SIZEX];

// init grid
for (int i = 0; i < SIZEY; i++){
            for(int j = 0; j < SIZEX; j++){
                    grid[i][j] = '#';
            }
    }

//init rand
srand(time(0));

//init stacks for xy coords
stack<int> xValues;
stack<int> yValues;

nGood = 0;
int direction = 0;

do{
    //find n good moves
    for (int i = 0; i < 4; i++){
        if (isGood(locX,locY,i,grid))
            nGood++;
    }

    // if only 1 good move, move there
    if (nGood == 1){
        if (isGood(locX,locY,NORTH,grid))
            locY = moveNS(NORTH,locY);
        else if (isGood(locX,locY,SOUTH,grid))
            locY = moveNS(SOUTH,locY);
        else if (isGood(locX,locY,EAST,grid))
                            locX = moveEW(EAST,locX);
                    else if (isGood(locX,locY,WEST,grid))
                            locX = moveEW(WEST,locX);
    }

    // if no good moves, move back in stack
    else if (nGood == 0){
        locX = xValues.top();
        locY = yValues.top();
        xValues.pop();
        yValues.pop();
    }

    //if more than 1 good move, push stack
    else if (nGood > 1){
        xValues.push(locX);
        yValues.push(locY);

        //direction to move randomly chosen
        do{
            direction = rand() % 4;
        }while (!isGood(locX,locY,direction,grid));

        locX = moveEW(direction,locX);
        locY = moveNS(direction,locY);
    }

    // set grid
    grid[locY][locX] = '.';
    //output grid to show creation
    printGrid(grid);
    //reset nGood value
            nGood = 0;

}while(!xValues.empty());

//final maze output
printGrid(grid);
return 0;
}
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1 回答 1

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如果在 isGood 函数中（grid[x][y] 而不是 grid[y][x]），你首先交换了 x 和 y。这至少有时会导致问题。

于 2012-01-11T15:26:14.283 回答