B - Intersection /

### 問題文

• 1 \le i \le N を満たす全ての整数 i について A_i \le x \le B_i

### 制約

• 1 \le N \le 100
• 1 \le A_i \le B_i \le 1000
• 入力に含まれる値は全て整数

### 入力

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


### 入力例 1

2
3 2
7 5


### 出力例 1

3


x3 \le x \le 72 \le x \le 5 の両方を満たさなければなりません。
そのような整数 x3, 4, 53 個あります。

### 入力例 2

3
1 5 3
10 7 3


### 出力例 2

0


### 入力例 3

3
3 2 5
6 9 8


### 出力例 3

2


Score : 200 points

### 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


### 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