module Main where
import Control.Monad
import Control.Applicative
import Data.Maybe
import Data.List
import qualified Text.Printf
import qualified Data.ByteString.Char8 as BC
import qualified Data.ByteString as BC

import Debug.Trace

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lowerBound :: (Integer -> Bool) -> Integer -> Integer -> Integer
lowerBound pred l r 
  | l + 1 >= r = r
  | otherwise =
    let m = (l + r) `div` 2 in 
      if pred m then lowerBound pred l m else lowerBound pred m r

main :: IO ()
main = do
  [a, b, c] <- map fromIntegral <$> readInts
  let f x = x + (x `div` a) * (b - 1)
  print $ lowerBound ((>= c) . f) 0 (10^18)
------------------------------------------

{- Int input -}

parseInt :: BC.ByteString -> Int
parseInt = fst . fromJust . BC.readInt

parseInts :: BC.ByteString -> [Int]
parseInts = map parseInt <$> BC.words

readInt :: IO Int
readInt = parseInt <$> BC.getLine

readInts :: IO [Int]
readInts = parseInts <$> BC.getLine

{- Double Formatting -}

doubleFmt :: Double -> String
doubleFmt = Text.Printf.printf "%.12f"