#include <bits/stdc++.h>
#define whlie while
#define pb push_back
#define eb emplace_back
#define fi first
#define se second
#define rep(i,N) for(int i = 0; i < (N); i++)
#define repr(i,N) for(int i = (N) - 1; i >= 0; i--)
#define rep1(i,N) for(int i = 1; i <= (N) ; i++)
#define repr1(i,N) for(int i = (N) ; i > 0 ; i--)
#define each(x,v) for(auto& x : v)
#define all(v) (v).begin(),(v).end()
#define sz(v) ((int)(v).size())
#define vrep(v,it) for(auto it = v.begin(); it != v.end(); it++)
#define vrepr(v,it) for(auto it = v.rbegin(); it != v.rend(); it++)
#define ini(...) int __VA_ARGS__; in(__VA_ARGS__)
#define inl(...) ll __VA_ARGS__; in(__VA_ARGS__)
#define ins(...) string __VA_ARGS__; in(__VA_ARGS__)
using namespace std; void solve();
using ll = long long; using vl = vector<ll>;
using vi = vector<int>; using vvi = vector< vector<int> >;
constexpr int inf = 1001001001;
constexpr ll infLL = (1LL << 61) - 1;
struct IoSetupNya {IoSetupNya() { cin.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(15); cerr << fixed << setprecision(7);} } iosetupnya;
template<typename T, typename U> inline bool amin(T &x, U y) { return (y < x) ? (x = y, true) : false; }
template<typename T, typename U> inline bool amax(T &x, U y) { return (x < y) ? (x = y, true) : false; }
template<typename T, typename U> ostream& operator <<(ostream& os, const pair<T, U> &p) { os << p.first << " " << p.second; return os; }
template<typename T, typename U> istream& operator >>(istream& is, pair<T, U> &p) { is >> p.first >> p.second; return is; }
template<typename T> ostream& operator <<(ostream& os, const vector<T> &v) { int s = (int)v.size(); rep(i,s) os << (i ? " " : "") << v[i]; return os; }
template<typename T> istream& operator >>(istream& is, vector<T> &v) { for(auto &x : v) is >> x; return is; }
void in(){} template <typename T,class... U> void in(T &t,U &...u){ cin >> t; in(u...);}
void out(){cout << "\n";} template <typename T,class... U> void out(const T &t,const U &...u){ cout << t; if(sizeof...(u)) cout << " "; out(u...);}
template<typename T>void die(T x){out(x); exit(0);}
#ifdef NyaanDebug
  #include "NyaanDebug.h"
  #define trc(...) do { cerr << #__VA_ARGS__ << " = "; dbg_out(__VA_ARGS__);} while(0)
  #define trca(v,N) do { cerr << #v << " = "; array_out(v , N);cout << endl;} while(0)
#else
  #define trc(...)
  #define trca(...)
  int main(){solve();}
#endif

using P = pair<ll,ll>; using vp = vector<P>;
constexpr int MOD = /** 1000000007; //*/ 998244353;
///////////////////////////////////////////////////////////

void solve(){
  ins(S); inl(K);
  int N = S.size();
  if(S.size() == 1) die(K / 2);
  if(S[0] != S[N-1]){
    ll ans = 0;
    rep(i,N-1) if(S[i] == S[i + 1]) ans++ , S[i + 1] = ' ';
    out(ans * K);
  }
  else{
    // 普通
    ll ans = 0;
    rep(i,N-1) if(S[i] == S[i + 1]) ans++ , i += 1;
    // S[0]を変える
    ll ans1 = 0;
    rep1(i,N-2) if(S[i] == S[i + 1]) ans1++ , i += 1;
    // S[N-1]を変える
    ll ans2 = 0;
    rep(i,N-2) if(S[i] == S[i + 1]) ans2++ , i += 1;
    // S[0]とS[N-1]を両方変える
    ll ans3 = 0;
    rep1(i,N-3) if(S[i] == S[i + 1]) ans3++ , i += 1;
    trc(ans , ans1 , ans2 , ans3);
    ll ret = ans + (K - 1) + (K - 1) * min(ans1 , ans2);
    trc(ret);
    if(ans + ans3 < min(ans1 , ans2) * 2){
      amin(ret , (ans3 + 2) * ( (K-1)/2) + (1 + min(ans1,ans2) )*( (K-1)&1) + ans*(K-(K-1)/2-((K-1)&1)) );
    }
    out(ret);
    
  }
}


Measured memory_bytes: 256