#include<bits/stdc++.h>

#define endl '\n'
#define pii pair<int, int>
#define int long long

using namespace std;

const int mod=1e9+7;

void solve(){
	int n,m;
	cin>>n>>m;

	vector<int>a(n+1);
	for(int i=1;i<=n;i++){
		cin>>a[i];
	}

	vector dp(n+10,vector<int>(n+10,-1));

	function<int(int,int)>dfs=[&](int l,int r){
		if((r-l+1)&1)return 0ll;
		if(l>r)return 1ll;
		if(dp[l][r]!=-1)return dp[l][r];
		int ans=0;
		if(a[l]>0){
			for(int i=l+1;i<=r;i+=2){
				if(a[i]==-a[l]){
					ans+=dfs(l+1,i-1)*dfs(i+1,r)%mod;
					ans%=mod;
				} else if(!a[i]){
					ans+=dfs(l+1,i-1)*dfs(i+1,r)%mod;
					ans%=mod;
				}
			}
		} else if(!a[l]){
			for(int i=l+1;i<=r;i+=2){
				if(!a[i]){
					ans+=m*dfs(l+1,i-1)%mod*dfs(i+1,r)%mod;
					ans%=mod;
				} else if(a[i]<0){
					ans+=dfs(l+1,i-1)*dfs(i+1,r)%mod;
					ans%=mod;
				}
			}
		}

		return dp[l][r]=ans;
	};

	cout<<dfs(1,n)<<endl;
	// cout<<1<<endl;
}

signed main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);

	int t;
	cin>>t;

	while(t--){
		solve();
	}

	
	return 0;
}