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 PHP7 (7.0.15) (judge verdict: Wrong Answer)

<?php
  $s = trim(fgets(STDIN));
  $k = trim(fgets(STDIN));
  
  $str_array = str_split($s);
  $cnt = count($str_array);
  $num = 0;
  $is_change = false;
  for($i = 1; $i < $cnt; $i++) {
    if ($str_array[$i] === $str_array[$i - 1] && !$is_change) {
      $num += 1;
      $is_change = true;
    } else {
      $is_change = false;
    }
  }
  echo $num * $k . PHP_EOL;