参考链接:
http://rapheal.iteye.com/blog/1526863
https://segmentfault.com/a/1190000002685939
http://m.blog.csdn.net/article/details?id=44992839
js实现深度和广度优先
http://www.jb51.net/article/81156.htm
js非递归实现遍历
http://www.html-js.com/article/2966
参考链接:
http://rapheal.iteye.com/blog/1526863
https://segmentfault.com/a/1190000002685939