#include <bits/stdc++.h>
using namespace std;
template <typename T>
T power(T a, long long b) {
  T r = 1;
  while (b) {
    if (b & 1) {
      r *= a;
    }
    a *= a;
    b >>= 1;
  }
  return r;
}
int inverse(int a, int m) {
  a %= m;
  if (a < 0) {
    a += m;
  }
  int b = m, u = 0, v = 1;
  while (a) {
    int t = b / a;
    b -= a * t;
    swap(a, b);
    u -= v * t;
    swap(u, v);
  }
  if (u < 0) {
    u += m;
  }
  return u;
}
template <int _P>
struct modnum {
  static constexpr int P = _P;

 private:
  int v;

 public:
  modnum() : v(0) {}
  modnum(long long _v) {
    v = _v % P;
    if (v < 0) {
      v += P;
    }
  }
  explicit operator int() const { return v; }
  bool operator==(const modnum& o) const { return v == o.v; }
  bool operator!=(const modnum& o) const { return v != o.v; }
  modnum inverse() const { return modnum(::inverse(v, P)); }
  modnum operator-() const { return modnum(v ? P - v : 0); }
  modnum operator+() const { return *this; }
  modnum& operator++() {
    v++;
    if (v == P) {
      v = 0;
    }
    return *this;
  }
  modnum& operator--() {
    if (v == 0) {
      v = P;
    }
    v--;
    return *this;
  }
  modnum operator++(int) {
    modnum r = *this;
    ++*this;
    return r;
  }
  modnum operator--(int) {
    modnum r = *this;
    --*this;
    return r;
  }
  modnum& operator+=(const modnum& o) {
    v += o.v;
    if (v >= P) {
      v -= P;
    }
    return *this;
  }
  modnum operator+(const modnum& o) const { return modnum(*this) += o; }
  modnum& operator-=(const modnum& o) {
    v -= o.v;
    if (v < 0) {
      v += P;
    }
    return *this;
  }
  modnum operator-(const modnum& o) const { return modnum(*this) -= o; }
  modnum& operator*=(const modnum& o) {
    v = (int)((long long)v * o.v % P);
    return *this;
  }
  modnum operator*(const modnum& o) const { return modnum(*this) *= o; }
  modnum& operator/=(const modnum& o) { return *this *= o.inverse(); }
  modnum operator/(const modnum& o) const { return modnum(*this) /= o; }
};
template <int _P>
ostream& operator<<(ostream& out, const modnum<_P>& n) {
  return out << int(n);
}
template <int _P>
istream& operator>>(istream& in, modnum<_P>& n) {
  long long _v;
  in >> _v;
  n = modnum<_P>(_v);
  return in;
}
using num = modnum<998244353>;
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n;
  num m;
  cin >> n >> m;
  vector<int> a(n);
  for (int i = 0; i < n; ++i) {
    cin >> a[i];
  }
  a.push_back(a[0]);
  int eq = 0;
  int neq = 0;
  for (int i = 0; i < n; ++i) {
    if (a[i] == a[i + 1]) {
      eq++;
    } else {
      neq++;
    }
  }
  vector<num> fact(n + 1), inv_fact(n + 1);
  fact[0] = inv_fact[0] = 1;
  for (int i = 1; i <= n; ++i) {
    fact[i] = fact[i - 1] * i;
    inv_fact[i] = inv_fact[i - 1] / i;
  }
  auto binom = [&](int x, int y) {
    return fact[x] * inv_fact[y] * inv_fact[x - y];
  };
  num cur = 0;
  for (int i = 0; i <= neq / 2; ++i) {
    cur += binom(neq, i);
  }
  num ans = 0;
  for (int i = 0, j = neq; i < neq; ++i, --j) {
    ans += power(m - 2, i) * (power(num(2), j) - cur) * binom(neq, i);
    if (j % 2 == 0) {
      cur -= binom(j, j / 2);
    }
    cur += binom(j - 1, (j - 1) / 2);
    cur /= 2;
  }
  cout << ans * power(m, eq) << "\n";
  return 0;
}
