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 (3.8.2) (judge verdict: Runtime Error)

S = list(input())
flag = False
if S[0] == S[1]:
    flag = True
N = len(S)
K = int(input())
cnt = 0

for i in range(N-1):
    if S[i] == S[i+1]:
        cnt += 1
        S[i+1] = '!'

if S[N-1] == S[0]:
    if flag:
        print(cnt*K)
    else:
        print(cnt*K+(K-1))
else:
    print(cnt*K)