import sys input=sys.stdin.readline def I(): return int(input()) def MI(): return map(int, input().split()) def LI(): return list(map(int, input().split())) def main(): mod=10**9+7 V,T,P=MI() V=V*(P+1) ans=1+V%(T-1) + (V//(T-1))*T if V%(T-1)==0: ans-=1 print(ans) main()