import sys
sys.setrecursionlimit(10**5)

n,q=map(int,input().split())
graph=[[] for _ in range(n)]
for _ in range(n-1):
    u,v=map(lambda x:int(x)-1,input().split())
    graph[u].append(v)
    graph[v].append(u)

sub=[0]*n
def sub_calc(v,p):
    sub[v]=1
    for nv in graph[v]:
        if nv==p:continue
        sub[v]+=sub_calc(nv,v)
    return sub[v]

sub_calc(0,-1)

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