它应该是一个广度优先搜索，标记父母的标签。当它完成后，追踪那些父母回到起点开始走路。
地图只是这些图块的数组
function Tile(x, y){
this.x = x;
this.y = y;
//for BFS
this.px = 0;
this.py = 0;
this.visited = false;
this.is = " ";
this.n = null;
this.e = null;
this.s = null;
this.w = null;
}
我不能为我的生活弄清楚它是我的算法还是我的起始数据。
如果有人可以帮我解决这个问题或将其清除为正确，我将非常感激。
function FakeBFS(){
var me = this;
this.get_path = function(sx, sy, ex, ey, map){
var x = sx;
var y = sy;
var unfinished = [{"x":sx, "y":sy}];
//walk until we can't or we reach our destination
while(unfinished.length && x != ex && y != ey){
var new_location = unfinished.shift();
x = new_location.x;
y = new_location.y;
//if we haven't been here...
if(map.tiles[x][y].visited == false){
console.log("\n\nlooking for path from:"+x+","+y+" to:"+ex+","+ey);
var nesw_array = new Array(
[x,y+1], //n
[x+1,y], //e
[x,y-1], //s
[x-1,y]);//w
console.log(nesw_array);
//add all the vertices we care about to unfinished
for(var nesw=0; nesw<4; nesw++){
var vx = nesw_array[nesw][0];
var vy = nesw_array[nesw][1];
console.log(nesw_array[nesw]);
if( (map.tiles[vx][vy].is == " "
|| map.tiles[vx][vy].is == "H")
&& map.tiles[vx][vy].visited == false){
console.log("parenting["+nesw+"]"+map.tiles[vx][vy].x+","+map.tiles[vx][vy].y+" to:"+x+","+y);
//set the route we took to get here
map.tiles[vx][vy].px = x;
map.tiles[vx][vy].py = y;
unfinished.push({"x":map.tiles[vx][vy].x, "y":map.tiles[vx][vy].y});
}
}
//visit this vertex
map.tiles[x][y].visited = true;
}
console.log("END LOOP looking for path from:"+x+","+y+" to:"+ex+","+ey);
}
//walk back to start for our path
var path = Array();
if(x == ex && y == ey){
while(x != sx && y != sy){
path.push({"x":x,"y":y});
console.log(x+","+y);
x = map.tiles[x][y].px;
y = map.tiles[x][y].py;
}
path.push({"x":x,"y":y});
console.log("Path:"+util.inspect(path));
return path;
}
return false;
}
}
我制作了一些样本数据，它基本上遇到了同样难以确定的问题。 在下面的代码中，“me”指的是Map（）对象。
function TestMap(){
var me = this;
this.paths = new Array();
//width and height
this.size = 10;
this.num_tiles = this.size*this.size;
//we can't build on the edge
this.start = 1;
this.end = this.size-this.start;
//
//
//tiles
////////////////////////////////////////
this.tiles = new Array();
//
//
//print
//////////////////////////////////////////
this.print = function(){
var mapscii = "";
for(var y=this.end; y>-1; y--){
for(var x=0; x<this.size; x++){
mapscii += this.tiles[x][y].is;
}
mapscii += "\n";
}
console.log(mapscii);
}
//
//
//setup the tile array and the associations
/////////////////////////////////////////////////
this.init_map = function (){
for(var x=0; x<me.size; x++){
me.tiles[x] = new Array();
for(var y=0; y<me.size; y++){
var t = new Tile(x, y);
//draw bounds
if(x==0 || y==0 || x==me.size-1 || y==me.size-1){
t.is = "#";
}
me.tiles[x][y] = t;
}
}
}
//
//
//setup the tile array and the associations
/////////////////////////////////////////////////
this.fake_map = function (){
var fake_rooms = [ [2,2]
, [2,3]
, [3,2]
//, [3,3]
//, [5,2]
, [5,3]
, [6,2]
, [6,3]
];
var fake_doors = [
[3,3]
, [5,2]
];
for(var x=0; x<fake_rooms.length; x++){
me.tiles[fake_rooms[x][0]][fake_rooms[x][1]].is = ".";
}
for(var x=0; x<fake_doors.length; x++){
me.tiles[fake_doors[x][0]][fake_doors[x][1]].is = "H";
}
}
this.fake_place_paths = function(){
var bfs = new BFS();
me.paths[0] = bfs.get_path(
3,3,
5,2,
me
);
}
this.mark_paths = function(){
for(var i=0; i<me.paths.length; i++){
console.log(me.paths);
var thispath = me.paths[i];
console.log("["+i+"]"+thispath.x+","+thispath.y);
me.tiles[thispath.x][thispath.y].is = "+";
}
}
this.init_map();
this.fake_map();
this.fake_place_paths();
this.print();
this.mark_paths();
}
这就是“假地图”在打印时的样子。
＃= Bounds
。 =房间
H =门
##########
# #
# #
# #
# #
# #
# .H .. #
# .. H. #
# #
##########
这是我的调试输出。
C:\Users\trans\Documents\JS>node test_bfs.js
looking for path from:3,3 to:5,2
[ [ 3, 4 ], [ 4, 3 ], [ 3, 2 ], [ 2, 3 ] ]
[ 3, 4 ]
parenting[0]3,4 to:3,3
[ 4, 3 ]
parenting[1]4,3 to:3,3
[ 3, 2 ]
[ 2, 3 ]
END LOOP looking for path from:3,3 to:5,2
looking for path from:3,4 to:5,2
[ [ 3, 5 ], [ 4, 4 ], [ 3, 3 ], [ 2, 4 ] ]
[ 3, 5 ]
parenting[0]3,5 to:3,4
[ 4, 4 ]
parenting[1]4,4 to:3,4
[ 3, 3 ]
[ 2, 4 ]
parenting[3]2,4 to:3,4
END LOOP looking for path from:3,4 to:5,2
looking for path from:4,3 to:5,2
[ [ 4, 4 ], [ 5, 3 ], [ 4, 2 ], [ 3, 3 ] ]
[ 4, 4 ]
parenting[0]4,4 to:4,3
[ 5, 3 ]
[ 4, 2 ]
parenting[2]4,2 to:4,3
[ 3, 3 ]
END LOOP looking for path from:4,3 to:5,2
looking for path from:3,5 to:5,2
[ [ 3, 6 ], [ 4, 5 ], [ 3, 4 ], [ 2, 5 ] ]
[ 3, 6 ]
parenting[0]3,6 to:3,5
[ 4, 5 ]
parenting[1]4,5 to:3,5
[ 3, 4 ]
[ 2, 5 ]
parenting[3]2,5 to:3,5
END LOOP looking for path from:3,5 to:5,2
looking for path from:4,4 to:5,2
[ [ 4, 5 ], [ 5, 4 ], [ 4, 3 ], [ 3, 4 ] ]
[ 4, 5 ]
parenting[0]4,5 to:4,4
[ 5, 4 ]
parenting[1]5,4 to:4,4
[ 4, 3 ]
[ 3, 4 ]
END LOOP looking for path from:4,4 to:5,2
looking for path from:2,4 to:5,2
[ [ 2, 5 ], [ 3, 4 ], [ 2, 3 ], [ 1, 4 ] ]
[ 2, 5 ]
parenting[0]2,5 to:2,4
[ 3, 4 ]
[ 2, 3 ]
[ 1, 4 ]
parenting[3]1,4 to:2,4
END LOOP looking for path from:2,4 to:5,2
END LOOP looking for path from:4,4 to:5,2
looking for path from:4,2 to:5,2
[ [ 4, 3 ], [ 5, 2 ], [ 4, 1 ], [ 3, 2 ] ]
[ 4, 3 ]
[ 5, 2 ]
parenting[1]5,2 to:4,2
[ 4, 1 ]
parenting[2]4,1 to:4,2
[ 3, 2 ]
END LOOP looking for path from:4,2 to:5,2
##########
# #
# #
# #
# #
# #
# .H .. #
# .. H. #
# #
##########
[ false ]
[0]undefined,undefined
C:\Users\trans\Documents\JS\testmap.js:102
me.tiles[thispath.x][thispath.y].is = "+";
^
TypeError: Cannot read property 'undefined' of undefined
at TestMap.mark_paths (C:\Users\trans\Documents\JS\testmap.js:102:24)
at new TestMap (C:\Users\trans\Documents\JS\testmap.js:110:7)
at Object.<anonymous> (C:\Users\trans\Documents\JS\test_bfs.js:2:11)
at Module._compile (module.js:570:32)
at Object.Module._extensions..js (module.js:579:10)
at Module.load (module.js:487:32)
at tryModuleLoad (module.js:446:12)
at Function.Module._load (module.js:438:3)
at Module.runMain (module.js:604:10)
at run (bootstrap_node.js:390:7)
答案 0 :(得分：0)
主要的问题是我离开循环的条件，还修改了我在获取数据之前引用的变量。
.......................
//walk until we can't or we reach our destination
while(unfinished.length){
var new_location = unfinished.shift();
x = new_location.x;
y = new_location.y;
if(x == ex && y == ey){
unfinished.length = 0;
continue;
}
..........................
//walk back to start for our path
var path = Array();
if(x == ex && y == ey){
console.log("here");
while(!(x == sx && y == sy)){
path.push({"x":x,"y":y});
console.log(x+","+y);
//temporary to not screw up reference
var tempx = map.tiles[x][y].px;
tempx = map.tiles[x][y].px;
y = map.tiles[x][y].py;
x = tempx;
console.log(x+","+y);
}
path.push({"x":x,"y":y});
return path;
}
return false;