#include<bits/stdc++.h>
using namespace std;
#define M 998244353
#define int long long
#define left 1
#define right 2
#define close 3
int t,c,n;
int p[500500];
int pos[500500];
int fa[500500];
int l[500500];
int r[500500];
int dir[500500];
int ljmp[500500],rjmp[500500];
int bt[500500];
void add(int x){
    for(;x<=n;x+=(x&-x))
        bt[x]++;
}
int qry(int x){
    int ret=0;
    for(;x;x-=(x&-x))ret+=bt[x];
    return ret;
}
int getfa(int x){
    if(x==fa[x])return x;
    fa[x]=getfa(fa[x]);
    return fa[x];
}
signed main(){
    scanf("%lld",&t);
    while(t--){
        scanf("%lld%lld",&n,&c);
        for(int i=1;i<=n;i++){
            scanf("%lld",p+i);
            pos[p[i]]=i;
            fa[i]=i;
            bt[i]=0;
            ljmp[i]=0;
            rjmp[i]=0;
            dir[i]=0;
        }
        for(int i=1;i<=n;i++){
            l[i]=pos[i];
            r[i]=pos[i];
        }
        for(int i=1;i<=n;i++){
            int curint=getfa(i);
            if(l[curint]==r[curint]){
                if(pos[curint]>c){
                    int lmost=p[pos[curint]-c];
                    lmost=getfa(lmost);
                    if(l[lmost]==r[lmost]){
                        if(qry(pos[curint]-c-1)==qry(pos[curint]-1)){
                            for(int i=pos[curint]-c;i<pos[curint]-1;i++)
                                fa[p[i]]=p[pos[curint]-1];
                            l[p[pos[curint]-1]]=pos[curint]-c;
                            r[p[pos[curint]-1]]=pos[curint]-1;
                            dir[p[pos[curint]-1]]=left;
                        }
                    }
                    else{
                        if(dir[lmost]==right){
                            for(int i=r[lmost]+1;i<pos[curint];i++)
                                fa[p[i]]=lmost;
                            r[lmost]=pos[curint]-1;
                            dir[lmost]=close;
                        }
                    }
                }
                if(pos[curint]+c<=n){
                    int rmost=p[pos[curint]+c];
                    rmost=getfa(rmost);
                    if(l[rmost]==r[rmost]){
                        if(qry(pos[curint]+c)==qry(pos[curint])){
                            for(int i=pos[curint]+2;i<=pos[curint]+c;i++)
                                fa[p[i]]=p[pos[curint]+1];
                            l[p[pos[curint]+1]]=pos[curint]+1;
                            r[p[pos[curint]+1]]=pos[curint]+c;
                            dir[p[pos[curint]+1]]=right;
                        }
                    }
                    else{
                        if(dir[rmost]==left){
                            for(int i=pos[curint]+1;i<l[rmost];i++)
                                fa[p[i]]=rmost;
                            l[rmost]=pos[curint]+1;
                            dir[rmost]=close;
                        }
                    }
                }
            }
            else{
                if(dir[curint]==left){
                    if(l[curint]<=c+1){
                        if(l[curint]!=1){
                            ljmp[curint]++;
                            for(int i=1;i<l[curint];i++)
                                fa[p[i]]=curint;
                            l[curint]=1;
                        }
                    }
                    else{//gengxin l,r
                        int lmost=p[l[curint]-c];//aaaaa
                        ljmp[curint]++;
                        lmost=getfa(lmost);
                        if(l[lmost]==r[lmost]){
                            for(int i=l[curint]-c;i<=l[curint]-1;i++)
                                fa[p[i]]=curint;
                            l[curint]=l[curint]-c;
                        }
                        else{
                            for(int i=r[lmost]+1;i<l[curint];i++)
                                fa[p[i]]=lmost;
                            fa[curint]=lmost;
                            r[lmost]=r[curint];
                            ljmp[lmost]=ljmp[curint];
                            dir[lmost]=close;
                        }
                    }
                }
                if(dir[curint]==right){
                    if(r[curint]+c>=n){
                        if(r[curint]!=n){
                            rjmp[curint]++;
                            for(int i=r[curint]+1;i<=n;i++)
                                fa[p[i]]=curint;
                            r[curint]=n;
                        }
                    }
                    else{//gengxin l,r
                        int rmost=p[r[curint]+c];//aaaa
                        rjmp[curint]++;
                        rmost=getfa(rmost);
                        if(l[rmost]==r[rmost]){
                            for(int i=r[curint]+1;i<=r[curint]+c;i++)
                                fa[p[i]]=curint;
                            r[curint]+=c;
                        }
                        else{
                            for(int i=r[curint]+1;i<l[rmost];i++)
                                fa[p[i]]=rmost;
                            fa[curint]=rmost;
                            l[rmost]=l[curint];
                            rjmp[rmost]=rjmp[curint];
                            dir[rmost]=close;
                        }
                    }

                }
            }
            //bt[pos[i]]++;
            add(pos[i]);
        }
        int ans=1;
        for(int i=1;i<=n;i++){
            int x=getfa(i);
            if(x==i){
                int len=r[x]-l[x]+1;
                //printf("%lld %lld %lld\n",x,l[x],r[x]);
                while(ljmp[x]){
                    ans=ans*ljmp[x]%M*c%M;
                    ljmp[x]--;
                    len--;
                }
                while(rjmp[x]){
                    ans=ans*rjmp[x]%M*c%M;
                    rjmp[x]--;
                    len--;
                }
                while(len){
                    ans=ans*len%M;
                    len--;
                }
            }
        }
        printf("%lld\n",ans);
    }
    return 0;
}