Wizards, Wands, and the Great Tower

In a world of magic, there are n young wizards who wish to enter the Great Tower of Sorcery to complete their final trials.
However, the Tower has a rule:

“No wizard may enter without holding a magic wand.”

There are k magic wands scattered along the Ancient Path, a straight road leading directly to the Tower, located at position p.
Each wizard starts at their own position along the path.
To enter the Tower, each wizard must:

1. First collect exactly one wand (each wand can be taken by only one wizard),
2. Then proceed to the Tower at position p.

• Wizards can pass by wands without picking them up.
• If two wizards reach a wand at the same time, only one can take it.
• All wizards move at one unit distance per second.

Your mission is to figure out the minimum possible time needed for all wizards to enter the Great Tower with wands.

Input Format

n k p
a1 a2 ... an
b1 b2 ... bk

• n: number of wizards
• k: number of wands
• p: position of the Tower
• a[i]: starting positions of wizards
• b[j]: positions of wands

Output Format

Minimum time for all wizards to enter the Great Tower.

Constraints

- 1 ≤ n ≤ 1000
- n ≤ k ≤ 2000
- 1 ≤ p, a[i], b[j] ≤ 10^9
- No two wizards or wands share the same starting position. But a wand and a wizard can share a same position.

Subtasks

• Subtask 1 (20 points): n, k ≤ 10
• Subtask 2 (10 points): n = 1
• No more subtasks

Sample Input 0

3 5 10
1 5 15
2 6 9 13 20

Sample Output 0

9