main.cpp

#include <bits/stdc++.h>
using namespace std;
using ll = long long;

const ll oo = numeric_limits<ll>::max();

struct Node {
  ll value;
  bool undef;
  Node() : value(1), undef(1){}; // Neutral element
  Node(ll v) : value(v), undef(0){};
};

inline Node combine(const Node &nl, const Node &nr) {
  if (nl.undef)
    return nr;
  if (nr.undef)
    return nl;
  Node m;
  m.value = gcd(nl.value, nr.value);
  m.undef = false;
  return m;
}

template <typename T = Node, auto F = combine> struct SegTree {
  int n;
  vector<T> st;
  SegTree(int _n) : n(_n), st(n << 1) {}

  void assign(int p, const T &k) {
    for (st[p += n] = k; p >>= 1;)
      st[p] = F(st[p << 1], st[p << 1 | 1]);
  }

  T query(int l, int r) {
    T ansl, ansr;
    for (l += n, r += n + 1; l < r; l >>= 1, r >>= 1) {
      if (l & 1)
        ansl = F(ansl, st[l++]);
      if (r & 1)
        ansr = F(st[--r], ansr);
    }
    return F(ansl, ansr);
  }
};

auto run() {
  int N;
  cin >> N;

  SegTree seg(N * 2);
  for (int i = 0; i < N; i++) {
    int xi;
    cin >> xi;
    seg.assign(i, xi);
    seg.assign(i + N, xi);
  }

  auto check = [&](int k) -> bool {
    int v = seg.query(0, k - 1).value;
    for (int i = 1; i < N; i++) {
      if (v != seg.query(i, i + k - 1).value)
        return false;
    }
    return true;
  };

  int ans = N;
  for (int l = 1, r = N; l <= r;) {
    int mid = (l + r) / 2;
    if (check(mid)) {
      ans = min(ans, mid);
      r = mid - 1;
    } else
      l = mid + 1;
  }

  cout << ans - 1 << '\n';
}

int32_t main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);

  int T;
  cin >> T;

  for (int i = 1; i <= T; i++)
    run();
}