Problem:
Score : 100 points

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."

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.

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

Solution in C++14 (GCC 5.4.1) (judge verdict: Accepted)

#include <bits/stdc++.h>

using namespace std;

int main(){
	int n, i;
	cin >> n >> i;
	int mid = (n % 2 == 0 ? n / 2 : n / 2 + 1);
	if(n % 2 == 0){
		cout << n - i + 1;   
	}
	else{
		if(i == mid)
			cout << i;
		else
			cout << n - i + 1;
	}
    return 0;
}