Problem Statement

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."

Input

Input is given from Standard Input in the following format:
N i

Output

Print the answer.

Constraints

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

Sample Input 1

4 2

Sample Output 1

3

The second car from the front of a 4-car train is the third car from the back.

Sample Input 2

1 1

Sample Output 2

1

Sample Input 3

15 11

Sample Output 3

5

见题面 Input 部分

见题面 Output 部分