#include <bits/stdc++.h>
using namespace std;
template <typename Tp>
inline void outarr(Tp _begin, Tp _end, const char* _delim = " ") {
  for (Tp current = _begin; current != _end; ++current) {
    std::cout << *current << _delim;
  }
  std::cout << '\n';
}
using ll = long long;
using pii = std::pair<int, int>;
constexpr int INF = 0x3f3f3f3f;
constexpr int MOD = static_cast<const int>(1e9 + 7);
constexpr int g_mod = 998244353;
int arr[200000];
int fact[200001];
int ifact[200001];
int Add(int x, int y) {
  x += y;
  return x < g_mod ? x : x - g_mod;
}
int Sub(int x, int y) {
  x -= y;
  return x >= 0 ? x : x + g_mod;
}
int Mul(int x, int y) { return int(1LL * x * y % g_mod); }
int FastPow(int x, int p) {
  int res = 1;
  while (p > 0) {
    if (p & 1) {
      res = Mul(res, x);
    }
    p >>= 1;
    x = Mul(x, x);
  }
  return res;
}
int Inv(int x) { return FastPow(x, g_mod - 2); }
void Init(int n) {
  fact[0] = 1;
  for (int i = 1; i <= n; ++i) {
    fact[i] = Mul(i, fact[i - 1]);
  }
  ifact[n] = Inv(fact[n]);
  for (int i = n - 1; i >= 0; --i) {
    ifact[i] = Mul(i + 1, ifact[i + 1]);
  }
}
int C(int k, int n) { return Mul(fact[n], Mul(ifact[k], ifact[n - k])); }
int Func(int len) {
  if (len & 1) {
    return 0;
  }
  return C(len >> 1, len);
}
int main() {
  std::ios_base::sync_with_stdio(false);
  std::cin.tie(nullptr);
  int n, k;
  cin >> n >> k;
  Init(n);
  for (int i = 0; i < (n); ++i) {
    cin >> arr[i];
  }
  int len = distance(arr, unique(arr, arr + n));
  if (arr[0] == arr[len - 1]) {
    --len;
  }
  if (len == 0) {
    return cout << (0) << '\n', 0;
    ;
  }
  const int inv2 = Inv(2);
  int k2 = (k - 2) % g_mod;
  int ans = 0;
  for (int i = 0; i < (len); ++i) {
    int cur =
        Mul(Sub(FastPow(2, len - i - 1), Mul(Func(len - i), inv2)), C(i, len));
    ans = Add(ans, Mul(FastPow(k2, i), cur));
  }
  ans = Mul(ans, FastPow(k % g_mod, n - len));
  cout << ans << "\n";
  return 0;
}
