Problem:
Score: 300 points

Problem Statement

In 2028 and after a continuous growth, AtCoder Inc. finally built an empire with six cities (City 1, 2, 3, 4, 5, 6)!

There are five means of transport in this empire:

Train: travels from City 1 to 2 in one minute. A train can occupy at most A people.

Bus: travels from City 2 to 3 in one minute. A bus can occupy at most B people.

Taxi: travels from City 3 to 4 in one minute. A taxi can occupy at most C people.

Airplane: travels from City 4 to 5 in one minute. An airplane can occupy at most D people.

Ship: travels from City 5 to 6 in one minute. A ship can occupy at most E people.

For each of them, one vehicle leaves the city at each integer time (time 0, 1, 2, ...).

There is a group of N people at City 1, and they all want to go to City 6.

At least how long does it take for all of them to reach there?
You can ignore the time needed to transfer.

Constraints

1 \leq N, A, B, C, D, E \leq 10^{15}

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N
A
B
C
D
E

Output

Print the minimum time required for all of the people to reach City 6, in minutes.

Sample Input 1

5
3
2
4
3
5

Sample Output 1

7

One possible way to travel is as follows.
First, there are N = 5 people at City 1, as shown in the following image:

In the first minute, three people travels from City 1 to City 2 by train. Note that a train can only occupy at most three people.

In the second minute, the remaining two people travels from City 1 to City 2 by train, and two of the three people who were already at City 2 travels to City 3 by bus. Note that a bus can only occupy at most two people.

In the third minute, two people travels from City 2 to City 3 by train, and another two people travels from City 3 to City 4 by taxi.

From then on, if they continue traveling without stopping until they reach City 6, all of them can reach there in seven minutes.

There is no way for them to reach City 6 in 6 minutes or less.

Sample Input 2

10
123
123
123
123
123

Sample Output 2

5

All kinds of vehicles can occupy N = 10 people at a time.
Thus, if they continue traveling without stopping until they reach City 6, all of them can reach there in five minutes.

Sample Input 3

10000000007
2
3
5
7
11

Sample Output 3

5000000008

Note that the input or output may not fit into a 32-bit integer type.

Solution in Haskell (GHC 7.10.3) (judge verdict: Wrong Answer)

--{-# LANGUAGE BangPatterns #-}
--{-# LANGUAGE ScopedTypeVariables #-}
--{-# LANGUAGE FlexibleContexts #-}
--{-# LANGUAGE ViewPatterns #-}
--{-# LANGUAGE OverloadedStrings #-}
--{-# LANGUAGE Strict #-}
--{-# LANGUAGE NumericUnderscores #-}
--{-# LANGUAGE BlockArguments #-}
{-# LANGUAGE MultiWayIf #-}
{-# LANGUAGE CPP #-}

import qualified Data.Vector as V
import qualified Data.Vector.Unboxed as VU
import qualified Data.Vector.Unboxed.Mutable as VUM
import qualified Data.ByteString.Char8 as BC
import qualified Data.Map.Strict as MPS
import qualified Data.Map as MP
import qualified Data.Set as ST
import qualified Data.Sequence as SQ
import Data.Array
-- import Data.Array.Unboxed
import Data.Array.ST
import Data.Array.IO
import Data.Maybe
import Data.Ord
import Data.Ratio
import Data.Char
import Data.Bits
import Data.List
import Data.Tuple
import Data.Functor
import Data.IORef
import Data.STRef
import Control.Applicative
import Control.Monad
import Control.Monad.ST
import Control.Monad.State.Strict
import Debug.Trace

#if __GLASGOW_HASKELL__ >= 808
import qualified Data.OrdPSQ as PSQ
import qualified Data.Vector.Algorithms.Merge as VAM
import qualified Data.Heap as HP
import Numeric.Extra
import Data.Tuple.Extra
import Data.List.Extra

data OrdQ = Ascending | Descending
#endif

---------------------------------------------------------------------------
main=do
    n<-int
    xs<-replicateM 5 int
    let
        m=minimum xs
        i=head$elemIndices m xs
    print $ i + (n `div` m)
--------------------------------------------------------------------------

-- Input Util
int :: IO Int
int = bsToInt <$> BC.getLine

double :: IO Double
double = bsToDouble <$> BC.getLine

str :: IO String
str = BC.unpack <$> BC.getLine

strBS :: IO BC.ByteString
strBS = BC.getLine

-- convert
bsToInt :: BC.ByteString -> Int
bsToInt = fst . fromJust . BC.readInt

bsToDouble :: BC.ByteString -> Double
bsToDouble = read . BC.unpack

bsToIntTuple :: BC.ByteString -> (Int, Int)
bsToIntTuple bs = (a,b)
    where
        Just (a,bs') = parseInt bs
        Just (b,_) = parseInt bs'

bsToIntTriple :: BC.ByteString -> (Int, Int, Int)
bsToIntTriple bs = (a,b,c)
    where
        Just (a,bs') = parseInt bs
        Just (b,bs'') = parseInt bs'
        Just (c,_) = parseInt bs''

parseInt :: BC.ByteString -> Maybe (Int, BC.ByteString)
parseInt = BC.readInt . BC.dropWhile isSpace

-- single line
fromSLineL :: (BC.ByteString -> a) -> IO [a]
fromSLineL f =  map f . BC.words <$> strBS

-- from single line to List / VU.Vector
sLineToIntL :: IO [Int]
sLineToIntL = fromSLineL bsToInt

sLineToDoubleL :: IO [Double]
sLineToDoubleL = fromSLineL bsToDouble

sLineToStrL :: IO [String]
sLineToStrL = fromSLineL BC.unpack

sLineToStrBSL :: IO [BC.ByteString]
sLineToStrBSL = fromSLineL id

sLineToIntV :: Int -> IO (VU.Vector Int)
sLineToIntV n = VU.unfoldrN n parseInt <$> BC.getLine

sLineToDoubleV :: IO (VU.Vector Double)
sLineToDoubleV = VU.fromList . map bsToDouble . BC.words <$> BC.getLine

-- multiple lines
fromMLinesL :: Int -> (BC.ByteString -> a) -> IO [a]
fromMLinesL n f = replicateM n (f <$> strBS)

fromMLinesV :: VU.Unbox a => Int -> (BC.ByteString -> a) -> IO (VU.Vector a)
fromMLinesV n f = VU.replicateM n (f <$> strBS)

-- from multiple lines to List / VU.Vector
mLinesToIntL :: Int -> IO [Int]
mLinesToIntL n = fromMLinesL n bsToInt

mLinesToDoubleL :: Int -> IO [Double]
mLinesToDoubleL n = fromMLinesL n bsToDouble

mLinesToStrL :: Int -> IO [String]
mLinesToStrL n = fromMLinesL n BC.unpack

mLinesToStrBSL :: Int -> IO [BC.ByteString]
mLinesToStrBSL n = fromMLinesL n id

mLinesToTupleL :: Int -> IO [(Int, Int)]
mLinesToTupleL n = fromMLinesL n bsToIntTuple

mLinesToTripleL :: Int -> IO [(Int, Int, Int)]
mLinesToTripleL n = fromMLinesL n bsToIntTriple

mLinesToIntV :: Int -> IO (VU.Vector Int)
mLinesToIntV n = fromMLinesV n bsToInt

mLinesToDoubleV :: Int -> IO (VU.Vector Double)
mLinesToDoubleV n = fromMLinesV n bsToDouble

mLinesToTupleV :: Int -> IO (VU.Vector (Int, Int))
mLinesToTupleV n = fromMLinesV n bsToIntTuple

mLinesToTripleV :: Int -> IO (VU.Vector (Int, Int, Int))
mLinesToTripleV n = fromMLinesV n bsToIntTriple

-- output
yesnoL :: Bool -> IO ()
yesnoL cond
    | cond = putStrLn "Yes"
    | otherwise = putStrLn "No"

yesnoU :: Bool -> IO ()
yesnoU cond
    | cond = putStrLn "YES"
    | otherwise = putStrLn "NO"

-- others
strToChr :: String -> Char
strToChr [x] = x

chrToStr :: Char -> String
chrToStr x = [x]

m1 :: Int -> Int
m1 = subtract 1

toDouble :: Int -> Double
toDouble = fromIntegral

toInt :: Double -> Int
toInt = floor

sqToList :: SQ.Seq a -> [a]
sqToList sq =
    case SQ.viewl sq of
        l SQ.:< sq' -> l : sqToList sq'
        SQ.EmptyL -> []

#if __GLASGOW_HASKELL__ >= 808
sortV :: (Ord a, VU.Unbox a) => VU.Vector a -> VU.Vector a
sortV v = VU.create $ do
    w <- VU.thaw v
    VAM.sort w
    return w

buildPQL :: Ord a => OrdQ -> [a] -> PSQ.OrdPSQ Int Int a
buildPQL oq xs =
    case oq of
        Ascending -> f $ zip3 [1..l] [1..l] $ sort xs
        Descending -> f $ zip3  [1..l] (map negate [1..l]) $ sort xs
    where
        l = length xs
        f = foldl' g PSQ.empty
        g acc (k,p,v) = PSQ.insert k p v acc

buildPQV :: (Ord a, VU.Unbox a) => OrdQ -> VU.Vector a -> PSQ.OrdPSQ Int Int a
buildPQV oq xs =
    case oq of
        Ascending -> f $ VU.zip3 (VU.generate l (+1)) (VU.generate l (+1)) $ sortV xs
        Descending -> f $ VU.zip3  (VU.generate l (+1)) (VU.generate l $ negate . (+1)) $ sortV xs
    where
        l = VU.length xs
        f = VU.foldl' g PSQ.empty
        g acc (k,p,v) = PSQ.insert k p v acc
#endif