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;
#define modulo 1000000007
#define mod(mod_x) ((((long long)mod_x+modulo))%modulo)
#define Inf 10000000000000000


int main(){
    
	string S;
	cin>>S;
	
	set<char> s;
	for(int i=0;i<S.size();i++){
		s.insert(S[i]);
	}
	
	long long K;
	cin>>K;
	
	long long ans = 0;
	
	if(s.size()!=1){
		for(int i=1;i<S.size();i++){
			if(S[i]==S[i-1]){
				ans++;
				S[i]='(';
			}
		}
		
		ans *= K;
		
		if(S[0]==S[S.size()-1]){
			ans += K-1;
		}
	}
	else{
		ans = (K*S.size())/2;
	}
	
	cout<<ans<<endl;
    
    
    return 0;
}