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.

Examples

Input

3 2

Output

2

Input

13 3

Output

11

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