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 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<stdio.h>
int main(void){
    char s[102];
    unsigned long long int k;
    scanf("%s",s);
    scanf("%llu",&k);
    unsigned long long int cnt=0;
    int flg=0;
    int cnt2=0;
    for(int i=1;s[i]!='\0';i++){
        if(s[i]==s[i-1]){
            if(s[i+1]=='\0'&&s[i]==s[0]){
                cnt++;
                flg=1;
                break;
            }
            if(s[i]==s[i+1]){
                 cnt2++;
                 i++;
            }
            cnt++;
            
        }
    }
    /*
    if(flg==1){
        cnt+=k-1;
    }*/
    //printf("%d %d\n",cnt,cnt2);
    //cnt==cnt-cnt2;
    cnt=cnt*k;
    printf("%llu\n",cnt);
    return 0;
}