题目描述
Problem Statement
You are given $a permutation p = (p_1, \ldots, p_N)$ of ${ 1, \ldots, N$ }.
You can perform the following two kinds of operations repeatedly in any order:
- Pay a cost A. Choose integers l and $r (1 \leq l < r \leq N)$, and shift $(p_l, \ldots, p_r)$ to the left by one. That is$, replace p_l, p_{l + 1}, \ldots, p_{r - 1}, p_r$ with $p_{l + 1}, p_{l + 2}, \ldots, p_r, p_l,$ respectively.
- Pay a cost B. Choose integers l and $r (1 \leq l < r \leq N)$, and shift $(p_l, \ldots, p_r)$ to the right by one. That is$, replace p_l, p_{l + 1}, \ldots, p_{r - 1}, p_r$ with $p_r, p_l, \ldots, p_{r - 2}, p_{r - 1},$ respectively.
Find the minimum total cost required to sort p in ascending order.
Input
Input is given from Standard Input in the following format:
N A B
$p_1 \cdots p_N$
Output
Print the minimum total cost required to sort p in ascending order.
Constraints
- All values in input are integers.
- $1 \leq N \leq 5000$
- $1 \leq A, B \leq 10^9$
- $(p_1 \ldots, p_N)$ is a permutation of ${ 1, \ldots, N$ }.
Sample Input 1
3 20 30
3 1 2
Sample Output 1
20
Shifting (p_1, p_2, p_3) to the left by one results in p = (1, 2, 3).
Sample Input 2
4 20 30
4 2 3 1
Sample Output 2
50
One possible sequence of operations is as follows:
- Shift (p_1, p_2, p_3, p_4) to the left by one. Now we have p = (2, 3, 1, 4).
- Shift (p_1, p_2, p_3) to the right by one. Now we have p = (1, 2, 3, 4).
Here, the total cost is 20 + 30 = 50.
Sample Input 3
1 10 10
1
Sample Output 3
0
Sample Input 4
4 1000000000 1000000000
4 3 2 1
Sample Output 4
3000000000
Sample Input 5
9 40 50
5 3 4 7 6 1 2 9 8
Sample Output 5
220
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分