Consecutive Integers

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

inputFormat

input are integers.

• 1 \leq K \leq N \leq 50

Input

Input is given from Standard Input in the following format:

N K

outputFormat

Output

Print the answer.

Examples

Input

3 2

Output

2

Input

13 3

Output

11

样例

13 3

11