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 Python (3.4.3) (judge verdict: Wrong Answer)

from itertools import combinations

N,K = map(int,input().split())
my_list = range(1,N)
x = combinations(my_list, K)
list_x = list(x)
len_y = len(list_x)
print(len_y)