1338A Powered Addition.cpp

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

template<class C> void mini(C&a, C b){ a=min(a, b);}
template<class C> void maxi(C&a, C b){a=max(a,b);}
#define sz(x) x.size()
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define mt make_tuple
#define forall(it,s) for(auto it = s.begin(); it != s.end(); ++it)
#define F0(i,n) for(int i = 0; i < n; i++)
#define F1(i,n) for(int (i) = 1; i <= n; i++)
#define F0R(i,n) for(int (i) = n-1; i >= 0; i--)
#define F1R(i,n) for(int (i) = n; i >= 1; i--)
#define REP(i,a,b) for(int i = a; i <= b; i++)
#define REPR(i,a,b) for(int i = a; i >= b; i--)
#define INF 1e9
#define todo(v) v.begin(),v.end()
#define eps 0.000000000001
#define mod 1000000007
#define PI acos(-1.0)
#define ll long long
#define fast ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);

typedef pair<int,int>   pii; 
typedef vector<int>     vi;   
typedef vector<ll>      vl;  
typedef vector<double>  vd;  
typedef vector<char>    vc;  
typedef vector<string>  vs;  
typedef set<int>        si;  
typedef set<ll>         sl;  
typedef set<double>     sd;  
typedef set<char>       sc;  
typedef set<string>     ss;  
typedef map<int,int>    mi;  
typedef map<ll,ll>      ml;  
typedef map<double,int> md;  
typedef map<char,int>   mc;  
typedef map<string,int> ms;  

void solve(){
	int n;
	cin >> n;
	vl a(n);
	F0(i,n) cin >> a[i];
	ll ans = 0;
	ll peak = a[0];
	ll actual;
	ll cont;
	F0(i,n) {
		if(peak >= a[i]){
			actual = peak - a[i];
			cont = 0;
			while(actual){
				actual >>= 1;
				cont++;
			}
			ans = max(ans, cont);
		}else{
			peak = a[i];
		}
	}
	cout << ans << endl;
}
int main(){
	int t;
	cin >> t;
	while(t--) solve();
	return 0;
}