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)

# coding: utf-8
S = input()
K = int(input())
l = [0]
tmp = 0
for i in range(len(S)-1):
    if S[i] == S[i+1]:
        # l.append(tmp + 1)
        tmp += 1
    else:
        if tmp > 0:
            l.append(tmp+1)
        tmp = 0
if tmp != 0:
    l.append(tmp+1)
ans = 0
ans += l[-1]//2
if S[0] == S[-1]:
    l[-1] += 1
for i in range(1, len(l)-1):
    ans += l[i]//2 * K
# print(ans)
ans += l[-1]//2 * (K-1)
# print(l)
print(ans)