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
	
	do @cnts :: #[n]int
	do bfs(g, 0, -1)
	
	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, parent: int): int
		var gc: list<int> :: g[current]
		do gc.head()
		var cnt: int :: 1
		for i(0, ^gc - 1)
			var neighbor: int :: gc.get()
			do gc.next()
			if(neighbor = parent)
				skip i
			end if
			do cnt :+ bfs(g, neighbor, current)
		end for
		do @cnts[current] :: cnt
		ret cnt
	end func
end func