func_code_string: #include <bits/stdc++.h>   using namespace std;   const int maxn = 3e5 + 17;   int N, Q;   int main() {     ios_base::sync_with_stdio(false);     cin >> Q;     while (Q--) {       cin >> N;       long long mx;       cin >> mx;       long long diff = 0;       while (--N) {         long long x;         cin >> x;         mx = max(mx, x);         diff = max(diff, mx - x);       }       long long ans = 0;       while (diff) {         ans++;         diff >>= 1;       }       cout << ans << endl;     }     return 0;   }   