var cnts: []int

func main()
	var n: int :: cui@inputInt()
	var q: int :: cui@inputInt()
	
	var g: []list<int> :: #[n]list<int>
	for i(0, n - 1)
		do g[i] :: #list<int>
	end for
	
	for(1, n - 1)
		var a: int :: cui@inputInt() - 1
		var b: int :: cui@inputInt() - 1
		do g[a].add(b)
		do g[b].add(a)
	end for
	
	; 部分木のサイズ
	do @cnts :: #[n]int
	do bfs(g, 0)
	
	var ans: int :: 0
	for(1, q)
		var p: int :: cui@inputInt() - 1
		var x: int :: cui@inputInt()
		do ans :+ @cnts[p] * x
		do cui@print("\{ans}\n")
	end for
	
	func bfs(g: []list<int>, current: int)
		var gCur: list<int> :: g[current]
		do gCur.head()
		do @cnts[current] :: 1
		for i(0, ^gCur - 1)
			var sub: int :: gCur.get()
			do gCur.next()
			if(@cnts[sub] = 0)
				do bfs(g, sub)
				do @cnts[current] :+ @cnts[sub]
			end if
		end for
	end func
end func