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
  
  $test = fgets(STDIN);
  $test =str_replace(PHP_EOL, '', $test);
  $num = (int)fgets(STDIN);
  $count = 0;
  $arr = str_split($test);
  $arr_size =  count($arr);
  for($i =0; $i < $arr_size; $i++){
     if ($i !== 0){
        if($arr[$i] == $arr[$i -1] ){
			$arr[$i] = "0";
       		$count++; 
       }
     }
   }
    echo $count * $num;

  ?>