Problem:
Score : 100 points

Problem Statement

We have two bottles for holding water.

Bottle 1 can hold up to A milliliters of water, and now it contains B milliliters of water.

Bottle 2 contains C milliliters of water.

We will transfer water from Bottle 2 to Bottle 1 as much as possible.

How much amount of water will remain in Bottle 2?

Constraints

All values in input are integers.

1 \leq B \leq A \leq 20

1 \leq C \leq 20

Input

Input is given from Standard Input in the following format:

A B C

Output

Print the integer representing the amount of water, in milliliters, that will remain in Bottle 2.

Sample Input 1

6 4 3

Sample Output 1

1

We will transfer two milliliters of water from Bottle 2 to Bottle 1, and one milliliter of water will remain in Bottle 2.

Sample Input 2

8 3 9

Sample Output 2

4

Sample Input 3

12 3 7

Sample Output 3

0

Solution in Scala (2.11.7) (judge verdict: Runtime Error)

object Main {

  def main(args: Array[String]): Unit = {
    val n = io.StdIn.readLine().toInt
    val hList = io.StdIn.readLine().split(" ").map(_.toInt).toList
    val answer = solve(n, hList)
    println(answer)
  }

  private def solve(n: Int, hList: List[Int]): String = {

    def loop(_list: List[Int], cur: Option[Int], operationCount: Int): String = {
      if (operationCount > 1) "No"
      else if (_list.isEmpty) "Yes"
      else if (cur.isEmpty) loop(_list.tail, Some(_list.head), operationCount)
      else if (_list.head - cur.get >= 0) loop(_list.tail, Some(_list.head), operationCount)
      else if (_list.head - cur.get >= 1) loop(_list.tail, Some(_list.head), operationCount + 1)
      else  "No"
    }

    loop(hList, None, 0)
  }

}