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 Fortran (gfortran v4.8.4) (judge verdict: Runtime Error)

PROGRAM ATCODER

implicit none
integer(16) :: n,i,j,count=0,count_a=0,count_b=0
character(len=10),allocatable :: s(:)

read*, n
allocate(s(n))
read*, s(1:n)

do i = 1, n
  do j = 1, len_trim(s(i))-1
    if ( s(i)(j:j+1) == 'AB' ) then
      count = count + 1
    end if
  end do
  if ( s(i)(1:1) == 'B' ) then
      count_b = count_b + 1
    end if   
    if ( s(i)(len_trim(s(i)):len_trim(s(i))) == 'A' ) then
      count_a = count_a + 1
    end if
end do

print'(i0)',  count + min(count_a,count_b)

END PROGRAM ATCODER