Problem:
Score : 100 points

Problem Statement

Snuke has N integers: 1,2,\ldots,N.
He will choose K of them and give those to Takahashi.

How many ways are there to choose K consecutive integers?

Constraints

All values in input are integers.

1 \leq K \leq N \leq 50

Input

Input is given from Standard Input in the following format:

N K

Output

Print the answer.

Sample Input 1

3 2

Sample Output 1

2

There are two ways to choose two consecutive integers: (1,2) and (2,3).

Sample Input 2

13 3

Sample Output 2

11

Solution in Haskell (GHC 7.10.3) (judge verdict: Accepted)

import qualified Data.Text as T
import qualified Data.Text.IO as T
import qualified Data.Text.Read as T

main :: IO ()
main = do
  (n : k : _) <- map unsafeSignedDecimal . T.words <$> T.getLine :: IO [Int]
  print (n - k + 1)

unsafeSignedDecimal :: T.Text -> Int
unsafeSignedDecimal s = case T.signed T.decimal s of
  Right (n, _) -> n