求高手解释一下这个随机迷宫算法

#include <iostream>
#include <ctime>
#include <cstdlib>
using namespace std;
#define MAZE_MAX 50
char map[MAZE_MAX+2][MAZE_MAX+2];
const int x = 11, y = 11;
int z1, z2;
 
void printMaze();
void makeMaze();
int searchPath(int, int);
int main()
{
    for(int i=0; i<=x*2+2; ++i)
        for(int j=0; j<=y*2+2; ++j)
            map[i][j] = 1;
 
    makeMaze();
    cout << "Tanky Woo" << endl;
    printMaze();
    return 0;
}
 
void printMaze()
{
    for(z2=1; z2<=y*2+1; z2++)
    {
        for(z1=1;z1<=x*2+1;z1++)
            fputs(map[z2][z1]==0?"　":"█",stdout);
        putchar(10);
    }
    cout << endl;
}
 
void makeMaze()
{
    for(z1=0, z2=2*y+2; z1<=2*x+2; ++z1)
    {
        map[z1][0] = 0;
        map[z1][z2] = 0;
    }
    for(z1=0, z2=2*x+2; z1<=2*y+2; ++z1)
    {
        map[0][z1] = 0;
        map[z2][z1] = 0;
    }
    map[2][1] = 0;
    map[2*x][2*y+1] = 0;
 
    srand((unsigned)time(NULL));
    searchPath(rand()%x+1, rand()%y+1);
}
 
int searchPath(int x, int y)
{
    static int dir[4][2] = {0, 1, 1, 0, 0, -1, -1, 0};
    int zx = x*2;
    int zy = y*2;
    int next, turn, i;
    map[zx][zy] = 0;
    turn = rand()%2 ? 1 : 3;
    for(i=0, next=rand()%4; i<4; ++i, next=(next+turn)%4)
        if(map[zx+2*dir[next][0]][zy+2*dir[next][1]] == 1)
        {
            map[zx+dir[next][0]][zy+dir[next][1]] = 0;
            searchPath(x+dir[next][0], y+dir[next][1]);
        }
    return 0;
}