module Main where

import Control.Monad.State

type Work = Int
type Day = Int

work :: Day -> State Work Day
work 1 = return 1
work daysLeft = do
    workToDo <- get
    let todaysWork = workToDo `div` daysLeft ^ 2
    put $ workToDo - todaysWork
    work $ daysLeft - 1

main :: IO()
main = do
    ws <- getLine
    ds <- getLine
    let w = read ws :: Int
    let d = read ds :: Int
    let (_, workOfLastDay) = runState (work d) w
    print workOfLastDay
    return ()