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)
cnt = 0
flg1 = False
flg2 = False
flg3 = False
flg4 = False
for i in range(N-1):
    if S[i] != S[i+1]:
        flg3 = True
        break
if (flg3 == False) and N % 2 == 1:
    print((N*K)//2)
    exit()
if (S[0] == S[N-1]) and K != 1:
    cnt += 1
    flg1 = True
if S[N-2] == S[N-1]:
    flg4 = True
for i in range(N-1):
    if flg2:
        flg2 = False
        continue
    if (i == N - 2) and flg1:
        break
    if S[i] == S[i+1]:
        cnt += 1
        flg2 = True
# print(cnt)
if flg1 and flg4 == False:
    print(cnt*K-1)
else:
    print(cnt*K)
# print(cnt*K)