#abc286c. [abc286_c]Rotate and Palindrome

[abc286_c]Rotate and Palindrome

Problem Statement

You are given a string SS of length NN. Let Si(1leqileqN)S_i\\ (1\\leq i \\leq N) be the ii-th character of SS from the left.

You may perform the following two kinds of operations zero or more times in any order:

  • Pay AA yen (the currency in Japan). Move the leftmost character of SS to the right end. In other words, change S1S2ldotsSNS_1S_2\\ldots S_N to S2ldotsSNS1S_2\\ldots S_NS_1.

  • Pay BB yen. Choose an integer ii between 11 and NN, and replace SiS_i with any lowercase English letter.

How many yen do you need to pay to make SS a palindrome?

What is a palindrome? A string TT is a palindrome if and only if the ii-th character from the left and the ii-th character from the right are the same for all integers ii (1leileT1 \\le i \\le |T|), where T|T| is the length of TT.

Constraints

  • 1leqNleq50001\\leq N \\leq 5000
  • 1leqA,Bleq1091\\leq A,B\\leq 10^9
  • SS is a string of length NN consisting of lowercase English letters.
  • All values in the input except for SS are integers.

Input

The input is given from Standard Input in the following format:

NN AA BB SS

Output

Print the answer as an integer.


Sample Input 1

5 1 2
rrefa

Sample Output 1

3

First, pay 22 yen to perform the operation of the second kind once: let i=5i=5 to replace S5S_5 with e. SS is now rrefe.

Then, pay 11 yen to perform the operation of the first kind once. SS is now refer, which is a palindrome.

Thus, you can make SS a palindrome for 33 yen. Since you cannot make SS a palindrome for 22 yen or less, 33 is the answer.


Sample Input 2

8 1000000000 1000000000
bcdfcgaa

Sample Output 2

4000000000

Note that the answer may not fit into a 3232-bit integer type.