import sys
import math
input = sys.stdin.readline
def read_values(): return map(int, input().split())
def read_index(): return map(lambda x: int(x) - 1, input().split())
def read_list(): return list(read_values())
from fractions import Fraction

def main():
  n,m,l=read_values()
  for i in range(60):
    v=1<<i
    print("?",2,i,flush=True)
    v0=int(input())
    if v!=v0:
      b=v-v0
      break
  print("!",pow(n,pow(m,l),b))
    
      
if __name__ == "__main__":
  main()