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 C++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<bits/stdc++.h>
using namespace std;

int main(){
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
string s;
cin >> s;
long long int k;
cin >> k;
long long int count = 0;
if (s[s.length()-1] == s[0]){
s += s[0];
}
for (int j = 1; j < s.length(); ++j){
if (s[j-1] == s[j]){
        ++count;
        if (j == s.length()-2){
break;
        }else{
++j;
        }
}
}

long long int a = count * k;
cout << a << "\n";
return 0;
}