atcoder#ABC286C. [ABC286C] Rotate and Palindrome

[ABC286C] Rotate and Palindrome

Score : 300300 points

Problem Statement

You are given a string SS of length NN. Let Si (1iN)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 S1S2SNS_1S_2\ldots S_N to S2SNS1S_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 T is a palindrome if and only if the i-th character from the left and the i-th character from the right are the same for all integers i (1 \le i \le |T|), where |T| is the length of T.

Constraints

  • 1N50001\leq N \leq 5000
  • 1A,B1091\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.

5 1 2
rrefa
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.

8 1000000000 1000000000
bcdfcgaa
4000000000

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