一个二维迷宫,判断一个人是否能从(0,0)要走到某个值为9的点,迷宫用2D数组表示,1为路,0为墙。请问以下代码的时间复杂度和空间复杂度?我有点绕晕了算不出来,谢谢!
public boolean find(int[][] grid){
if(grid==null || grid.length==0 || grid[0].length==0 || grid[0][0]==0) return 0;
return helper(grid,0,0);
}
private boolean helper(int[][] grid,int x, int y){
if(x>=0&&x<grid.length&&y>=0&y<grid[0].length){
if(grid[x][y]==0) return false;
else if(grid[x][y]==9) return true;
else if(grid[x][y]==1){
grid[x][y]=2;
return helper(grid,x,y-1)||helper(grid,x+1,y)||helper(grid,x,y+1)||helper(grid,x-1,y);
}
else return false;
}
else return false;
}