类似于[NOI2021]轻重边的逆过程，操作1即为对$u$执行access（根为1），$dist(u,v)$即为$u$到$v$的虚边数 对前者用LCT维护，并记录轻重边的切换，显然切换总量为$o(n\log n)$ 换言之，问题即要支持： 1.修改一条边的边权（实边边权为0，虚边边权为1），共$o(n\log n)$次 2.查询两点间的带权距离
原文链接：http://www.cnblogs.com/nickchan/archive/2011/10/09/3104473.html Apple has lost a visionary and creative genius, and the world has lost an amazing human being. Those of us who have been fortunate enough to konw and work with
原文链接：http://www.cnblogs.com/carefree/archive/2007/10/31/944536.html It's been a long road Getting from there to here It's been a long time But my time is finally near And I can feel the change in the wind right now Nothin
