update()里如果(x <= l && r <= y) 的话不用pushdown啊
by sfmmdm @ 2019-07-31 18:02:37
@[clt19](/space/show?uid=79058) sfmmdm说得对
by luogu_618 @ 2019-08-04 11:12:05
谢谢各位！
by clt19 @ 2019-08-05 12:49:12