该程序是对树进行先深、先广遍历，请在此基础上，改为处理指定图，求该图从指定结点出发的先深、先广遍历生成树。-The tree program is the first deep, wide first traversal, in this basis, to handle the specified map, find the graph starting from the specified node of the first deep, wide traverse the spanning tree first.