#define _CRT_SECURE_NO_WARNINGS
#include "bits/stdc++.h"
using namespace std;
#define rep(i, n) for(int i=0; i<(n); ++i)
#define repi(n) for(int i=0; i<(n); ++i)
#define repj(n) for(int j=0; j<(n); ++j)
#define repk(n) for(int k=0; k<(n); ++k)
#define FOR(i, m, n) for(int i=(m); i<(n); ++i)
#define sz(x) ((int)(x).size())
#define all(x) (x).begin(),(x).end()
#define mp make_pair
#define pb push_back
#define dump(x) cerr << #x << " = " << (x) << endl;
#define qp(f) [](auto i){return f;}
using LL=long long;
using VI=vector<int>;
using VL=vector<LL>;
using VS=vector<string>;
using VVI=vector<vector<int>>;
using PII=pair<int, int>;
const int inf = (int)1e9;
const LL MOD = 1000000007;
const double pi = acos(-1.0);
template<class T>T Sort(T & a) { sort(a.begin(), a.end()); return a; }
template<class T>T ReSort(T& a) { sort(a.rbegin(), a.rend()); return a; }
template<class T>T Reverse(T& a) { reverse(a.begin(), a.end()); return a; }
template<class T>void Unique(T& a) { a.erase(unique(a.begin(), a.end()), a.end()); }
template<class T>auto Max(T a) { return *max_element(a.begin(), a.end()); }
template<class T>auto Min(T a) { return *min_element(a.begin(), a.end()); }
template<class T, class U>int Count(T a, U c) { return count(a.begin(), a.end(), c); }
template<class T, class U>U Sum(T a, U init = 0) { return accumulate(a.begin(), a.end(), init); }
template<class T>T Age(T a, T b) { return (a + b - 1) / b; }
template<class T>T gcd(T n, T m) { return m == 0 ? n : gcd(m, n % m); }
template<class T>T lcm(T n, T m) { return n / gcd(n, m) * m; }
struct SORT {}SOrt;
template<class T> T operator |(T v, SORT s) {
	return Sort(v);
}
char Snum[] = "0123456789";


/* MOD */
LL modpow(LL a, LL n, LL _MOD = MOD) {
	LL re = 1;
	while (n > 0) {
		if (n & 1)re = re * a % _MOD;
		a = a * a % _MOD; n >>= 1;
	}
	return re;
}
LL modinv(LL n, LL _MOD = MOD) {
	return modpow(n, _MOD - 2, _MOD);
}
struct Modl {
	LL val = 0;
	Modl(LL v = 0)noexcept :val(v% MOD) { if (val < 0)v += MOD; }
	operator LL() { return val; }
};
Modl operator-(const Modl & a) { Modl r; r.val = a.val ? MOD - a.val : 0; return r; }
Modl operator+(const Modl & a, const Modl & b) { Modl r(a.val + b.val); return r; }
Modl operator-(const Modl & a, const Modl & b) { Modl r(a.val - b.val); return r; }
Modl operator*(const Modl & a, const Modl & b) { Modl r(a.val * b.val); return r; }
Modl operator/(const Modl & a, const Modl & b) { Modl r(a.val * modinv(b.val, MOD)); return r; }

Modl operator+(const Modl & a, const int& b) { Modl r(a.val + LL(b)); return r; }
Modl operator-(const Modl & a, const int& b) { Modl r(a.val - LL(b)); return r; }
Modl operator*(const Modl & a, const int& b) { Modl r(a.val * LL(b)); return r; }
Modl operator/(const Modl & a, const int& b) { Modl r(a.val * modinv(LL(b), MOD)); return r; }

Modl operator+(const Modl & a, const LL & b) { Modl r(a.val + b); return r; }
Modl operator-(const Modl & a, const LL & b) { Modl r(a.val - b); return r; }
Modl operator*(const Modl & a, const LL & b) { Modl r(a.val * b); return r; }
Modl operator/(const Modl & a, const LL & b) { Modl r(a.val * modinv(b, MOD)); return r; }

Modl operator+(const int& a, const Modl & b) { Modl r(LL(a) + b.val); return r; }
Modl operator-(const int& a, const Modl & b) { Modl r(LL(a) - b.val); return r; }
Modl operator*(const int& a, const Modl & b) { Modl r(LL(a) * b.val); return r; }
Modl operator/(const int& a, const Modl & b) { Modl r(LL(a) * modinv(b.val, MOD)); return r; }

Modl operator+(const LL & a, const Modl & b) { Modl r(a + b.val); return r; }
Modl operator-(const LL & a, const Modl & b) { Modl r(a - b.val); return r; }
Modl operator*(const LL & a, const Modl & b) { Modl r(a * b.val); return r; }
Modl operator/(const LL & a, const Modl & b) { Modl r(a * modinv(b.val, MOD)); return r; }
Modl pow(Modl a, int n) { Modl r(modpow(a, n)); return r; }
Modl pow(Modl a, LL n) { Modl r(modpow(a, n)); return r; }

/* INPUT */
struct inputter_Str {
	vector<string> inputbuffer;
	string operator [](int n) { while (inputbuffer.size() <= n) { string s; cin >> s; inputbuffer.push_back(s); }return inputbuffer[n]; }
	operator string() { return this[inputbuffer.size()]; }
}; inputter_Str in;
struct inputter_Int {
	int operator [](int n) { return stoi(in[n]); }
	operator int() { return stoi(string(in)); }
}; inputter_Int ini;
struct inputter_LL {
	LL operator [](int n) { return stoll(in[n]); }
	operator int() { return stoll(string(in)); }
}; inputter_LL inl;
struct inputter_Double {
	double operator [](int n) { return stod(in[n]); }
	operator int() { return stold(string(in)); }
}; inputter_Double ind;
VI invi(int n, int m) { VI v(m); for (int i = 0; i < m; ++i)v[i] = ini[n + i]; return v; }
VL invl(int n, int m) { VL v(m); for (int i = 0; i < m; ++i)v[i] = inl[n + i]; return v; }
int Suminvi(int n, int m) { return Sum(invi(n, m), 0); }LL Suminvl(int n, int m) { return Sum(invl(n, m), 0LL); }
int Maxinvi(int n, int m) { return  Max(invi(n, m)); }LL Maxinvl(int n, int m) { return Max(invl(n, m)); }
int Mininvi(int n, int m) { return  Min(invi(n, m)); }LL Mininvl(int n, int m) { return Min(invl(n, m)); }

/* OUTPUT */
struct boolswitch { string t, f; boolswitch(string tr, string fa) :t(tr), f(fa) {} }yes("yes", "no"), Yes("Yes", "No"), YES("YES", "NO"), Yay("Yay!", ":(");
struct divizer { string s; divizer(string s_) :s(s_) {} }spc(" "), nosp("");
struct outputter {
	bool flag = false; boolswitch bs; divizer di;
	outputter(bool f, boolswitch b, divizer d) :flag(f), bs(b), di(d) {}
	template<class T>outputter operator ,(T o) {
		if (flag)cout << di.s; cout << o;
		outputter t(true, bs, di); return t;
	}
	outputter operator ,(double o) {
		if (flag)cout << di.s; printf("%.20f", o);
		outputter t(true, bs, di); return t;
	}
	outputter operator ,(bool o) {
		if (flag)cout << di.s; cout << (o ? bs.t : bs.f);
		outputter t(true, bs, di); return t;
	}
	template<class T> outputter operator ,(vector<T> o) {
		if (flag)cout << di.s;
		for (int i = 0; i < (int)o.size(); ++i)cout << o[i] << (i == (int)o.size() - 1 ? "" : di.s);
		outputter t(true, bs, di); return t;
	}
	outputter operator ,(outputter o) { cout << '\n'; return o; }
	outputter operator ,(boolswitch b) { outputter t(flag, b, di); return t; }
	outputter operator ,(divizer d) { outputter t(flag, bs, d); return t; }
}out(false, Yes, spc);

/* ANSWER */
struct Answer {
	int mini = INT_MAX, maxi = INT_MIN, sumi = 0;
	LL minl = LLONG_MAX, maxl = LLONG_MIN, suml = 0LL;
	double mind = DBL_MAX, maxd = DBL_MIN, sumd = 0.;
	int count = 0;
	void operator =(int n) { mini = min(mini, n); maxi = max(maxi, n); sumi += n; count++; }
	void operator =(LL n) { minl = min(minl, n); maxl = max(maxl, n); suml += n; count++; }
	void operator =(double n) { mind = min(mind, n); maxd = max(maxd, n); sumd += n; count++; }
}ans;

int main() {
	VI a(100, inf * 2);
	a[0] = 0;
	a[1] = 1;
	a[2] = 3;
	a[3] = 7;
	a[4] = 15;
	FOR(i, 5, 1000) {
		a[i] = (a[i - 1] + 1) * 2 - 1;
		if (a[i] > 1000000000)break;
	}

	rep(i, 95) {
		if (a[i] <= ini[0])ans = i;
	}
	out, ans.maxi, out;
}


Measured memory_bytes: 3240