import sys
input = sys.stdin.readline

N=int(input())

EDGE=[list(map(int,input().split())) for i in range(N-1)]

E=[[] for i in range(N+1)]

for x,y in EDGE:
    E[x].append(y)
    E[y].append(x)

X=[-1]*(N+1)
X[1]=0

Q=[1]

while Q:
    x=Q.pop()

    for to in E[x]:
        if X[to]==-1:
            X[to]=X[x]^1
            Q.append(to)

LIST=[]
for i in range(1,N+1):
    if X[i]==0:
        LIST.append(i)

SET=set(LIST)
Q=[]
for i in range(N-1):
    x,y=EDGE[i]

    if x in SET:
        Q.append(x)
    else:
        Q.append(y)

print("?",*Q,flush=True)
ret=input().strip()

if ret=="Yes":
    pass
else:
    LIST=[]
    for i in range(1,N+1):
        if X[i]==1:
            LIST.append(i)


while len(LIST)>1:
    LIST2=LIST[:len(LIST)//2]
    SET=set(LIST2)
    SET2=set(LIST[len(LIST)//2:])

    Q=[]
    for i in range(N-1):
        x,y=EDGE[i]

        if x in SET:
            Q.append(x)
        elif y in SET:
            Q.append(y)
        elif x in SET2:
            Q.append(y)
        elif y in SET2:
            Q.append(x)
        else:
            Q.append(y)

    print("?",*Q,flush=True)
    ret=input().strip()

    if ret=="Yes":
        LIST=LIST2
    else:
        LIST=LIST[len(LIST)//2:]

print("!",LIST[0],flush=True)