Cannot figure out what is wrong with this PARPER code

help
1

My logic is the exact same as the editorial, however it is giving WA, I have tried as many test cases as possible (all outputs being correct), even checked for long long, % 1e9 + 7 errors, etc. Can anyone figure out what is wrong with this code?

#include <iostream>
#include <algorithm>
#include <vector>
#include <string>
#include <cmath>
#include <iterator>
#include <set>
#include <map>
#include <numeric>
#include <unordered_set>
using namespace std;

typedef long long ll;
typedef vector<int> vi;

#define PB push_back
#define F first
#define S second
#define M 1000000007ll

ll fact(ll n)
{
    ll fact = 1, i;
    for (i = 2; i <= n; i++)
        fact *= i; fact %= M;
    return fact;
}

void solve() {
    ll n; int k; ll a;
    cin >> n >> k; vector<ll> as(n);
    bool odd = false; bool even = false;
    ll co = 0; ll ce = 0;
    for (ll i = 0; i < n; i++) {
        cin >> as[i]; 
        if (as[i] % 2) {odd = true; co += 1;} else {even = true; ce += 1;}
    }
    if (k == 0) {
        if (odd && even) {cout << 0 << "\n";}
        else {
            cout << fact(n) << "\n";
        }
    }
    else {
        if (n % 2) {
            if (abs(co - ce) == 1) {
                cout << (fact(n / 2 + 1) * fact(n / 2)) % M << "\n";
            }
            else {
                cout << 0 << "\n";
            }
        }
        else {
            if (co == ce) {
                cout << ((fact(n / 2) * fact(n / 2) % M) * 2) % M << "\n";
            }
             else {
                cout << 0 << "\n";
            }
        }
    }
}

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0); 
    ll t;
    cin >> t;
    while(t--) {solve();}
}