Problem:
Score : 100 points

Problem Statement

Joisino wants to evaluate the formula "A op B".
Here, A and B are integers, and the binary operator op is either + or -.
Your task is to evaluate the formula instead of her.

Constraints

1≦A,B≦10^9

op is either + or -.

Input

The input is given from Standard Input in the following format:

A op B

Output

Evaluate the formula and print the result.

Sample Input 1

1 + 2

Sample Output 1

3

Since 1 + 2 = 3, the output should be 3.

Sample Input 2

5 - 7

Sample Output 2

-2

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

import Data.Char
import Data.List

main::IO ()
main = do
    s <- getLine
    let a = read $ head $ group s
    let b = read $ last $ group s
    print $ if (s !! 2) == '+' then a+b else a-b