Envío 6111

Código

N = int(input())

arbol = {}
for i in range(N-1):
    arbolData = input().split() #[0, 1] 0 is ancestor and 1 is child
    # key=child and value=parent  {'1':'0'}
    arbol['0'] = None
    arbol[arbolData[1]] = arbolData[0]


c = int(input())
for i in range(c):
    query = input().split(' ')
    ancestor = query[0]
    child   = query[1]

    if ancestor == child:
        print('Yes')

    parent = arbol[child]
    while parent is not None:
        if parent == ancestor:
            print('Yes')
            break
    
    print('No')