import pypyjit
pypyjit.set_param('max_unroll_recursion=-1')

n,q = map(int,input().split())

edge = [[] for _ in range(n)]
for _ in range(n-1):
    a,b = map(int,input().split())
    edge[a-1].append(b-1)
    edge[b-1].append(a-1)
    
cnt = [0]*n

def dfs(x,p):
    ret = 1
    for c in edge[x]:
        if c == p:
            continue
        ret += dfs(c,x)
    cnt[x] += ret
    return ret

dfs(0,-1)

ans = 0
for _ in range(q):
    p,x = map(int,input().split())
    ans += cnt[p-1]*x
    print(ans)