#include<bits/stdc++.h>
using namespace std;
using ll=long long;
#define rep(i, a, b) for(int i = a; i < (b); i++)
const ll mod = 998244353;

int main() {
    int n, m;
    cin >> n >> m;
    vector<ll> a(n);
    rep(i, 0, n) cin >> a[i];

    int diff = a[0] + a[n-1];
    rep(i, 1, n) if (a[i] != a[i-1]) diff++;

    vector<ll> dp(n+2);
    dp[diff] = 1;

    rep(i, 0, m) {
        vector<ll> ndp(n+2);

        rep(j, 0, n+2) {
            // 境目を二つ選ぶ方法は j * (j - 1) / 2
            if (j - 2 >= 0) ndp[j-2] += dp[j] * ((j * (j - 1) / 2) % mod) % mod;

            // 境目を一つ選ぶ方法は j * (n + 1 - j)
            ndp[j] += dp[j] * ((j * (n + 1 - j)) % mod) % mod;

            // 境目を選ばない方法は (n + 1 - j) * (n - j) / 2
            if (j + 2 <= n + 1) ndp[j+2] += dp[j] * (((n + 1 - j) * (n - j) / 2) % mod) % mod;
        }
        rep(j, 0, n+2) ndp[j] %= mod;
        dp.swap(ndp);
    }

    cout << dp[0] << endl;
}