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 Python (3.4.3) (judge verdict: Wrong Answer)

s=input()
k=int(input())
n=len(s)
if n==1:
    print(k//2)
    exit()
if n==2:
    if s[0]==s[1]:
        print(k)
    else:
        print(0)
    exit()
tc=1
ac=0
p=s[0]
for i in range(1,n):
    if s[i]==p:
        tc+=1
    else:
        ac+=tc//2
        tc=1
        p=s[i]
else:
    ac+=tc//2
ans=ac*k
if s[0]==s[-1]:
    if s[0]!=s[1] and s[-1]!=s[-2]:
        ans+=k//2
print(ans)