CPP0218.cpp

#include <bits/stdc++.h>
#define MAX 10000001
#define ll long long
#define fastsync()                    \
    ios_base::sync_with_stdio(false); \
    cin.tie(NULL);                    \
    cout.tie(NULL);
const int mod = 1e9 + 7;
using namespace std;

int main() {
    fastsync();
    int t;
    cin >> t;
    while (t--) {
        int n;
        cin >> n;
        int cnt = 0, ans = 0, j = 1, a[n];
        for (int i = 0; i < n; ++i)
            cin >> a[i];
        if (n)
            while (a[j] == a[j - 1])
                ++j;
        ans = abs(a[j - 1] - a[j]);
        for (int i = j + 1; i < n; ++i)
            ans = __gcd(ans, abs(a[i] - a[i - 1]));
        if (j == n)
            ans = 0;
        double sq = sqrt(ans);
        for (int i = 1; i <= sq; ++i) {
            if (ans % i == 0) {
                cnt++;
                if (ans / i != i)
                    cnt++;
            }
        }
        cout << cnt << endl;
    }
    return 0;
}