"""

https://yukicoder.me/problems/no/1830

前半と後半で分ける？
まず、0項目をAとする

ラストがBの場合、最初と最後を除いた区間が答え
ラストもAの場合は

真ん中で切る
左右のうち、Bが多いほうを角から二分探索。
A=Bとなる区間を見つける

補集合が答え


"""

import sys
from sys import stdin

N = int(stdin.readline())
askdic = {}
askdic[N] = N//2

def ask(i,side):

    if side == "L":
        if i in askdic:
            return askdic[i]
        print ("?",i,flush=True)
        cat = int(stdin.readline())
        askdic[i] = cat
        return askdic[i]

    else:
        askind = N-i
        if askind in askdic:
            return N//2 - askdic[askind]
        print ("?",askind,flush=True)
        cat = int(stdin.readline())
        askdic[askind] = cat
        return N//2 - askdic[askind]

def getAB(rangenum,askans):

    if l1 == 0:
        return askans , rangenum - askans
    else:
        return rangenum - askans, askans

#N = int(stdin.readline())

l1 = ask(1,"L")
r1 = ask(1,"R")

if l1 != r1:
    print ("!",2,N-1,flush=True)
    sys.exit()

else:

    leftA,leftB = getAB(N//2, ask(N//2,"L") )
    
    if leftA <= N//2:
        l = 1
        r = N//2
        while r-l != 1:
            m = (l+r)//2
            mA,mB = getAB(m , ask(m,"L") )
            if mA <= mB:
                r = m
            else:
                l = m

        print ("!",r+1,N,flush=True)
        sys.exit()

    else:
        l = 1
        r = N//2
        while r-l != 1:
            m = (l+r)//2
            mA,mB = getAB(m , ask(m,"R") )
            if mA <= mB:
                r = m
            else:
                l = m

        print ("!",1,N-r,flush=True)
        sys.exit()