迭代bfsvarlevelorder=function (根) if (! root(return () /为空的baseletstack=[ root ] le tres=[ ] while ) stack.length0) { let count=stack.length //每一层icount; I ) let root=stack.shift (RES [ RES.length-1 ].push (root.val ) /保存值//保存节点root.leftstack.push ) root .
递归DFS必须传递到当前级别
varlevelorder=function (根) if (! 根(返回) ) letRES=) let level=0功能搜索(根,级别) ) if (! root (返回空值(! res[level](RES[level]=[] ) RES[level].push(root.val ) levelsearch (root.left,level ) search ) root )