There is an N-car train.

You are given an integer i. Find the value of j such that the following statement is true: "the i-th car from the front of the train is the j-th car from the back."

Constraints

• $1 \leq N \leq 100$
• $1 \leq i \leq N$

Input

Input is given from Standard Input in the following format:

N i

Output

Print the answer.

Examples

Input

4 2

Output

3

Input

1 1

Output

1

Input

15 11

Output

5

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