import sys
input = lambda :sys.stdin.readline()[:-1]
ni = lambda :int(input())
na = lambda :list(map(int,input().split()))
yes = lambda :print("yes");Yes = lambda :print("Yes");YES = lambda : print("YES")
no = lambda :print("no");No = lambda :print("No");NO = lambda : print("NO")
#######################################################################


T, sx, sy, gx, gy = na()

def dist(a, b):
    return abs(a[0] - b[0]) + abs(a[1] - b[1])

ok = 0
ng = T
while ng - ok > 1:
    mid = ok + ng >> 1
    print("?", mid, flush=True)
    x, y = na()
    if dist((x, y), (sx, sy)) <= dist((x, y), (gx, gy)):
        ok = mid
    else:
        ng = mid

print("!", ok)