Problem:
Score : 300 points

Problem Statement

Given is a string S. Let T be the concatenation of K copies of S.
We can repeatedly perform the following operation: choose a character in T and replace it with a different character.
Find the minimum number of operations required to satisfy the following condition: any two adjacent characters in T are different.

Constraints

1 \leq |S| \leq 100

S consists of lowercase English letters.

1 \leq K \leq 10^9

K is an integer.

Input

Input is given from Standard Input in the following format:

S
K

Output

Print the minimum number of operations required.

Sample Input 1

issii
2

Sample Output 1

4

T is issiiissii. For example, we can rewrite it into ispiqisyhi, and now any two adjacent characters are different.

Sample Input 2

qq
81

Sample Output 2

81

Sample Input 3

cooooooooonteeeeeeeeeest
999993333

Sample Output 3

8999939997

Solution in C# (Mono 4.6.2.0) (judge verdict: Wrong Answer)

using System;
using System.Linq;

public class Hello
{
    public static void Main()
    {
        char[] text = Console.ReadLine().Trim().ToArray();
        int count = int.Parse(Console.ReadLine().Trim());
        
        int result = 0;
        for (int i = 1; i < text.Length; i++)
        {
            if (text[i] != text[i - 1]) continue;
            text[i] = '0';
            result++;
        }
        
        if (text.Last() == text[0])
        {
            result++;
        }
        
        Console.WriteLine(result * count);
    }
}