Black dot = = white dot (MST)

Black spot == White spot （MST）

The question ：

Let's give a connected graph with no phase , Each edge may be black or white , Ask if there is a spanning tree structure that makes the number of black edges on the tree == Number of white edges

$2\le n\le 1e5,1\le m\le 1e5$
Ideas ：

1. Regard the black edge weight as 1, The weight of the white edge is regarded as 0, For any value between the minimum spanning tree and the maximum spanning tree edge weight sum , There are corresponding spanning trees

2. Obvious ： One of the minimum spanning trees 0 Edge deletion , Then the minimum spanning tree weight is at most +1, thus , For any value between the minimum spanning tree and the maximum spanning tree edge weight sum , There are corresponding spanning trees .

（ Isn't this a doll ？ So it's obvious : )