#include #include #include using namespace std; typedef long long ll; int main() { ios::sync_with_stdio(false); cin.tie(0); int n; cin>>n; vector a(n); for (int i=0;i<n;++i) cin>>a[i]; vector b(n); b[0]=a[0]+1; int max_j=1; for (int i=1;i<n;++i) { ll need=b[i-1]-a[i]; if (need<=0) { b[i]=a[i]+1; max_j=max(max_j,1); } else { int j=0; while (need>0) { need-=(1LL << (2j))-1; ++j; } b[i]=a[i]+(1LL << (2j))-1; max_j=max(max_j,j); } } cout<<max_j<<endl; return 0; }