#include <string.h>
#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <cfloat>
#include <climits>
#include <cmath>
#include <complex>
#include <ctime>
#include <deque>
#include <fstream>
#include <functional>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <list>
#include <map>
#include <memory>
#include <queue>
#include <random>
#include <set>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>
using namespace std;

constexpr int mod = 998244353;

void mpl(int &x,int y) {
    x += y;
    if(x >= mod) x -= mod;
}

long long modpow(long long a,long long b) {
    long long ans = 1;
    while(b) {
        if(b & 1) {
            (ans *= a) %= mod;
        }
        (a *= a) %= mod;
        b /= 2;
    }
    return ans;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int t;
    cin >> t;
    while(t--) {
        int n,m;
        cin >> n >> m;
        vector<int>x(n);
        int cnt = 0,tmp = 0;
        for(int i = 0; i < n; i++) {
            cin >> x[i];
            if(x[i] == -1) {
                cnt++;
            }
            else {
                tmp += x[i];
                tmp %= m;
            }
        }
        if(cnt == 0) {
            if(tmp == 0) {
                int ans = 0;
                for(int i = 0; i < n; i++) {
                    tmp += x[i];
                    tmp %= m;
                    if(tmp) ans++;
                }
                cout << ans << "\n";
                continue;
            }
            cout << 0 << "\n";
            continue;
        }
        int res = 0,sum = 0;
        int ans = 0;
        for(int i = 0; i < n; i++) {
            if(x[i] == -1) {
                res++;
                if(res == cnt) {
                    if(sum != tmp) {
                        mpl(ans,modpow(m,cnt-1));
                    }
                    continue;
                }
                mpl(ans,modpow(m,cnt-2)*(m-1)%mod);
            }
            else {
                sum += x[i];
                sum %= m;
                if(res == 0 && sum == 0) continue;
                if(res == 0) {
                    mpl(ans,modpow(m,cnt-1));
                    continue;
                }
                if(res == cnt) {
                    if(sum != tmp) {
                        mpl(ans,modpow(m,cnt-1));
                    }
                    continue;
                }
                mpl(ans,modpow(m,cnt-2)*(m-1)%mod);
            }
        }
        cout << ans << "\n";
    }
}