#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using ll = long long;
using namespace atcoder;
using mint = modint998244353;

int n,m,a[5005],b[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]) b[i] = 1,cnt++;
        else b[i] = 0;
    }
    vector<mint> dp(n + 2,0);
    dp[cnt] = 1;
    for(int i = 0; i < m; i++){
        vector<mint> ndp(n + 2,0);
        for(int j = 0; j <= n + 1; j++){
            if(j >= 2) ndp[j - 2] += dp[j] * j * (j - 1) / 2;
            ndp[j] += dp[j] * j * (n + 1 - j);
            if(j + 2 <= n + 1) ndp[j + 2] += dp[j] * (n + 1 - j) * (n - j) / 2;
        }
        swap(dp,ndp);
        cout << endl;
    }
    cout << dp[n + 1].val(); 
}