求改错，悬赏一只小滑稽

P4234 最小差值生成树

![](http://ww1.sinaimg.cn/bmiddle/ceeb653ejw1fc2d1q4obnj20dw0dwdhl.jpg)
by GLReturno_O @ 2018-08-20 10:06:44

![](http://ww1.sinaimg.cn/bmiddle/ceeb653ejw1fc2d1q4obnj20dw0dwdhl.jpg)
by 塔罗兰 @ 2018-08-20 10:09:08

![](http://ww1.sinaimg.cn/bmiddle/ceeb653ejw1fc2d1q4obnj20dw0dwdhl.jpg)
by Gypsophila @ 2018-08-20 10:11:51

![前排出售滑稽](http://ww1.sinaimg.cn/bmiddle/ceeb653ejw1fc2d1q4obnj20dw0dwdhl.jpg)
by tllwtg @ 2018-08-20 10:14:28

![img](http://ww1.sinaimg.cn/bmiddle/ceeb653ejw1fc2d1q4obnj20dw0dwdhl.jpg)
by M_sea @ 2018-08-20 10:18:00

![](http://ww1.sinaimg.cn/bmiddle/ceeb653ejw1fc2d1q4obnj20dw0dwdhl.jpg)
by Steinway @ 2018-08-20 10:19:51

http://ww1.sinaimg.cn/bmiddle/ceeb653ejw1fc2d1q4obnj20dw0dwdhl.jpg
by ghy21 @ 2018-08-20 10:22:06