Problem Description

Takahashi is organizing old photos from his childhood.

While organizing, he found a wooden box containing photos and decided to organize them by pasting them into an album. To determine the size of the album needed, he wants to know the number of photos in the box.

Takahashi has numbered all his photos with positive integers, and the box contains all photos with serial numbers from $ S $ to $ T $ inclusive.

Takahashi wants to know the number of photos in the box, but counting them one by one is cumbersome.

You are to write a program that calculates the number of photos pasted in the album from the values of $ S $ and $ T $.

Input Format

The input is given from the standard input in the following format:

$ S $ $ T $

• The first line contains two integers $S, T\ (1\ ≦\ S\ ≦\ T\ ≦\ 1,000)$ representing the range of serial numbers of the photos in the album.

Output Format

Output the number of photos in the box. Ensure a newline at the end of the output.

Sample Input and Output

Sample Input #1

4 7

Sample Output #1

4

Sample Input #2

1 1

Sample Output #2

1

Notes/Hints

Sample Explanation 1

The serial numbers $ 4 $, $ 5 $, $ 6 $, and $ 7 $ correspond to a total of $ 4 $ photos.

Sample Explanation 2

Only the photo with the serial number $ 1 $ is relevant.

见题面 Input 部分

见题面 Output 部分