#include <bits/stdc++.h>
using namespace std;
using ll = long long;
constexpr ll mod = 998244353;
constexpr ll inv = 499122177;

int n,m,a[5005],cnt;
int main(){
    cin >> n >> m;
    a[0] = 0,a[n + 1] = 0;
    for(int i=1;i<=n;i++) cin >> a[i];
    for(int i = 0; i <= n; i++){
        if(a[i] == a[i + 1]) cnt++;
    }
    vector<ll> dp(n + 2,0);
    vector<ll> ndp(n + 2,0);
    dp[cnt] = 1;
    for(int i = 0; i < m; i++){
        for(int j = 0; j <= n + 1; j++){
            if(j >= 2) ndp[j - 2] += (((dp[j] * j * (j - 1)) % mod) * inv) % mod;
            ndp[j] += (dp[j] * j * (n + 1 - j)) % mod;
            if(j + 2 <= n + 1) ndp[j + 2] += ((dp[j] * (n + 1 - j) * (n - j)) % mod * inv) % mod;
        }
        for(int j = 0; j <= n + 1; j++) ndp[j] %= mod;
        swap(dp,ndp);
        fill(ndp.begin(), ndp.end(), 0);
    }
    cout << dp[n + 1]; 
}