图模板：树上问题

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n = len(edges)+1
m = n.bit_length()
g = [[] for _ in range(n)]
for u,v in edges: 
	g[u].append(v)
	g[v].append(u)
D = [0]*n
f = [[-1]*m for _ in range(n)]
sk = [(0,-1)]
while sk:
	u,fa = sk.pop()
	for i in range(m-1):
		p = f[u][i]
		if p!=-1:
			f[u][i+1] = f[p][i]
	for v in g[u]:
		if v!=fa:
			sk.append((v,u))
			f[v][0] = u
			D[v] = D[u]+1

def lca(x,y):    
	if D[x]>D[y]:
		x,y = y,x
	k = D[y]-D[x]
	for i in range(k.bit_length()):
		if k>>i&1:
			y = f[y][i]
	if x!=y:
		for i in range(m-1,-1,-1):
			px,py = f[x][i],f[y][i]
			if px!=py:
				x,y = px,py
		x = f[x][0]
	return x

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n = len(edges)+1
g = [[] for _ in range(n)]
for u,v in edges:
	g[u].append(v)
	g[v].append(u)
D,sz = [0]*n,[0]*n
fa,son = [-1]*n,[-1]*n
top = list(range(n))
sons = []

def dfs(u):
	sz[u] = 1
	for v in g[u]:
		if v!=fa[u]:
			D[v] = D[u]+1
			fa[v] = u
			dfs(v)
			sz[u] += sz[v]
			if son[u]==-1 or sz[v]>sz[son[u]]:
				son[u] = v
	if son[u]!=-1:
		sons.append(son[u])
dfs(0)
for u in sons[::-1]:
	top[u] = top[fa[u]]
		
def lca(x,y):
	while top[x]!=top[y]:
		x,y = (fa[top[x]],y) if D[top[x]]>D[top[y]] else (x,fa[top[y]])
	return x if D[x]<D[y] else y

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def dvd(u):
	def cal(core):
		pass
		
	def dfs(u,fa):
		sz[u] = 1
		w[u] = 0
		A.append(u)
		for v in g[u]:
			if v!=fa and not vis[v]:
				dfs(v,u)
				sz[u] += sz[v]
				w[u] = max(w[u],sz[v])
	A = [] 
	dfs(u,-1)
	core = min(A,key=lambda x:max(w[x],sz[u]-sz[x]))
	cal(core)
	vis[core] = 1
	for v in g[core]:
		if not vis[v]:
			dvd(v)

n = len(edges)+1
g = [[] for _ in range(n)]
for u,v in edges:
	g[u].append(v)
	g[v].append(u)
res = [0]*n
vis = [0]*n
sz = [0]*n
w = [0]*n
dvd(0)
return res