import sys
sys.setrecursionlimit(10**7)
readline = sys.stdin.readline

def dfs(s, p=-1):
    n = 1
    for u in G[s]:
        if u == p:
            continue
        n += dfs(u, s)
    dp[s] = n
    return n

N, Q = map(int, readline().split())
G = [[] for i in range(N)]
for i in range(N - 1):
    A, B = map(int, readline().split())
    A, B = A - 1, B - 1
    G[A].append(B)
    G[B].append(A)
    
dp = [0] * N
dfs(0)
ans = 0
for _ in range(Q):
    p, x = map(int, readline().split())
    p -= 1
    ans += dp[p] * x
    print(ans)