101991: [AtCoder]ABC199 B - Intersection

Problem Statement

You are given sequences of length $N$ each: $A = (A_1, A_2, A_3, \dots, A_N)$ and $B = (B_1, B_2, B_3, \dots, B_N)$.
Find the number of integers $x$ satisfying the following condition:

• $A_i \le x \le B_i$ holds for every integer $i$ such that $1 \le i \le N$.

Constraints

• $1 \le N \le 100$
• $1 \le A_i \le B_i \le 1000$
• All values in input are integers.

Input

Input is given from Standard Input in the following format:

$N$
$A_1$ $A_2$ $A_3$ $\dots$ $A_N$
$B_1$ $B_2$ $B_3$ $\dots$ $B_N$

Output

Print the answer.

Sample Input 1

2
3 2
7 5

Sample Output 1

3

$x$ must satisfy both $3 \le x \le 7$ and $2 \le x \le 5$.
There are three such integers: $3$, $4$, and $5$.

Sample Input 2

3
1 5 3
10 7 3

Sample Output 2

0

There may be no integer $x$ satisfying the condition.

Sample Input 3

3
3 2 5
6 9 8

Sample Output 3

2