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 Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Scanner;

/*
 * AtCoder Beginner Contest 107 A "Train"
 *   https://abc107.contest.atcoder.jp/tasks/abc107_a/
 */
public class Main {

	public static void main(String[] args) {

		InputScanner in = new InputScanner(System.in);
		PrintWriter out = new PrintWriter(System.out);

		Task task = new Task();
		task.run(in, out);

		in.close();
		out.close();
	}

	static class Task {

		public void run(InputScanner in, PrintWriter out) {

			int N = in.nextInt();
			int i = in.nextInt();

			out.println(N - i + 1);
		}
	}

	/*
	 * extends java.util.Scanner
	 */
	static class InputScanner {

		Scanner scanner;

		public InputScanner(InputStream inputStream) {
			this.scanner = new Scanner(inputStream);
		}

		public boolean hasNext() {
			return scanner.hasNext();
		}

		public int nextInt() {
			return Integer.parseInt(scanner.next());
		}

		public long nextLong() {
			return Long.parseLong(scanner.next());
		}

		public double nextDouble() {
			return Double.parseDouble(scanner.next());
		}
		public String next() {
			return scanner.next();
		}

		public int[] nextIntArray(int n) {
			int[] ret = new int[n];
			for (int i = 0; i < n; i++) {
				ret[i] = scanner.nextInt();
			}
			return ret;
		}

		public int[][] nextIntArray(int h, int w) {
			int[][] ret = new int[h][w];
			for (int i = 0; i < h; i++) {
				for (int j = 0; j < w; j++) {
					ret[i][j] = scanner.nextInt();
				}
			}
			return ret;
		}

		public long[] nextLongArray(int n) {
			long[] ret = new long[n];
			for (int i = 0; i < n; i++) {
				ret[i] = scanner.nextLong();
			}
			return ret;
		}

		public long[][] nextlongArray(int h, int w) {
			long[][] ret = new long[h][w];
			for (int i = 0; i < h; i++) {
				for (int j = 0; j < w; j++) {
					ret[i][j] = scanner.nextLong();
				}
			}
			return ret;
		}

		public double[] nextDoubleArray(int n) {
			double[] ret = new double[n];
			for (int i = 0; i < n; i++) {
				ret[i] = scanner.nextDouble();
			}
			return ret;
		}

		public double[][] nextDoubleArray(int h, int w) {
			double[][] ret = new double[h][w];
			for (int i = 0; i < h; i++) {
				for (int j = 0; j < w; j++) {
					ret[i][j] = scanner.nextLong();
				}
			}
			return ret;
		}

		public String[] nextStringArray(int n) {
			String[] ret = new String[n];
			for (int i = 0; i < n; i++) {
				ret[i] = scanner.next();
			}
			return ret;
		}

		public String[] nextStringArray(String split) {
			String[] ret = scanner.next().split(split);
			return ret;
		}

		public String[][] nextStringArray(int h, int w) {
			String[][] ret = new String[h][w];
			for (int i = 0; i < h; i++) {
				for (int j = 0; j < w; j++) {
					ret[i][j] = scanner.next();
				}
			}
			return ret;
		}

		public String[][] nextStringArray(int h, String split) {
			String[][] ret = new String[h][];
			for (int i = 0; i < h; i++) {
				ret[i] = scanner.next().split(split);
			}
			return ret;
		}

		public void close() {
			scanner.close();
		}

	}

}