#include<cstdio>
#include<cstring>
#include<algorithm>
#include<vector>
#include<bitset>

#define fi first
#define se second
#define mkp std::make_pair
using ll=long long;
using std::min;
using std::max;
template<class T> void cmax(T&a,T b){a=max(a,b);}
template<class T> void cmin(T&a,T b){a=min(a,b);}

const ll mod=998244353;
int C[505][505],fac[505];

namespace xm{
    int N,K,q[505],g[505],f[505][505];
    void _(){
        scanf("%d%d",&N,&K);

        fac[0]=1;
        for(ll i=1;i<=N;++i) fac[i]=fac[i-1]*i%mod;
        for(int i=0;i<=N;++i){
            C[i][0]=1;
            for(int j=1;j<=i;++j)
                C[i][j]=(C[i-1][j-1]+C[i-1][j])%mod;
        }
        for(int i=1;i<=N;++i){
            f[i][1]=fac[i];
            for(int j=1;j<=i;++j)
            for(int k=1;i+k<=N;++k)
                f[i+k][j+1]=(f[i+k][j+1]+(ll)fac[k]*f[i][j])%mod;
        }

        bool F=1;
        for(int i=1;i<=N;++i){
            scanf("%d",&q[i]);
            if(q[i]!=i) F=false;
        }
        if(F){
            ll ans=0;
            for(int i=N;i>=K;--i){
                g[i]=f[N][i];
                for(int j=i+1;j<=N;++j)
                    g[i]=(g[i]+(mod-g[j])*C[j-1][i-1])%mod;
                ans=(ans+g[i])%mod;
            }
            printf("%lld\n",ans);
            return;
        }
        int t=1;
        while(q[t]<q[t+1]) ++t;
        for(int i=t;i;--i){
            g[i]=f[t][i];
            for(int j=i+1;j<=t;++j)
                g[i]=(g[i]+(mod-g[j])*C[j-1][i-1])%mod;
        }
        ll ans=0;
        for(int s=t+1;s<=N;++s){
            if(s>t+1&&(q[s]<q[t]||q[s]<q[s-1])) break;
            int c=K+s-N-1;
            if(c<1) continue;
            ans=(ans+(ll)fac[s-t-1]*g[c])%mod;
        }
        printf("%lld\n",ans);
    }
}

int main(){
    xm::_();
    return 0;
}