from collections import *
from itertools import *
from functools import *
from heapq import *
import sys,math
# input = sys.stdin.readline

N,Q = map(int,input().split())
e = [[] for _ in range(N)]
for i in range(N-1):
  a,b = map(int,input().split())
  a -= 1
  b -= 1
  e[a].append(b)
  e[b].append(a)

dist = [-1]*N
def dfs(x):
  if(x!=0):
    if len(e[x]) == 1:
        return
  for ix in e[x]:
    if dist[ix] == -1:
      dist[ix] = dist[x] + 1
      dfs(ix)
  return
dist[0] = 0
dfs(0)
flg = [-1]*N
def dfs_v2(x):
  if(x!=0):
    if len(e[x]) == 1:
        flg[x] = 1
        return 1
  if flg[x] != -1:
    return flg[x]
  tmp = 1
  for ix in e[x]:
    if dist[ix] > dist[x]:
      tmp += dfs_v2(ix)
  flg[x] = tmp
  return tmp
dfs_v2(0)
S = 0
for _ in range(Q):
  p,x = map(int,input().split())
  p -= 1
  S += x*flg[p]
  print(S)
# print(flg)