# import sys
# #sys.setrecursionlimit(1000000)
# input = sys.stdin.readline
def mp():return map(int,input().split())
def lmp():return list(map(int,input().split()))
import math
import bisect
from copy import deepcopy as dc
from itertools import accumulate
from collections import Counter, defaultdict, deque
import itertools
def ceil(U,V):return (U+V-1)//V
def modf1(N,MOD):return (N-1)%MOD+1
inf = int(1e30)
mod = int(1e9+7)

n,Q = mp()
edge = [[] for i in range(n)]
for i in range(n-1):
    a,b = mp()
    a -= 1
    b -= 1
    edge[a].append(b)
    edge[b].append(a)
num = [[] for i in range(n)]
num[0].append(0)
kaisou = [0]*n
q = deque([0])
used = [0]*n
used[0] = 1
while q:
    here = q.popleft()
    for i in edge[here]:
        if not used[i]:
            used[i] += 1
            kaisou[i] = kaisou[here] + 1
            num[kaisou[i]].append(i)
            q.append(i)
size = [1]*n
for i in num[::-1]:
    for j in i:
        for k in edge[j]:
            if kaisou[j] - 1 == kaisou[k]:
                size[k] += size[j]
# print(num)
# print(size)
ans = 0
for _ in range(Q):
    p,x = mp()
    p -= 1
    ans += size[p]*x
    print(ans)