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

// #define int long long

#define GET_MACRO(a, b, c, d, NAME, ...) NAME
#define REP2(i, n) REP3(i, 0, n)
#define REP3(i, a, b) REP4(i, a, b, 1)
#define REP4(i, a, b, s) for (ll i = (a); i < (ll)(b); i += s)
#define RREP2(i, n) RREP3(i, 0, n)
#define RREP3(i, a, b) for (ll i = (b) - 1; i >= (ll)(a); i--)

#define rep(...) GET_MACRO(__VA_ARGS__, REP4, REP3, REP2)(__VA_ARGS__)
#define rrep(...) GET_MACRO(__VA_ARGS__,, RREP3, RREP2)(__VA_ARGS__)
#define eb emplace_back
#define ef emplace_front
#define pb pop_back
#define pf pop_front
#define all(c) begin(c), end(c)
#define mp make_pair
#define mt make_tuple
#define fi first
#define se second
#define popcnt __builtin_popcountll

#ifdef DEBUG
	#define dump(x) cerr << "line " << __LINE__ << " : " << #x " = " << x << endl;
#else
	#define dump(x)
#endif

using uint = unsigned;
using ll = long long;
using ull = unsigned long long;
using ld = long double;
using vi = vector<int>;
using vvi = vector<vi>;

template<typename T>
using maxheap = priority_queue<T, vector<T>, less<T>>;

template<typename T>
using minheap = priority_queue<T, vector<T>, greater<T>>;

const int INF = 1e9 + 10;
const ll LLINF = 1e18 + 10;

const int dx[] = {-1, 0, 1, 0, -1, 1, 1, -1};
const int dy[] = {0, -1, 0, 1, -1, -1, 1, 1};

template<typename T>
inline T sq(T x){
	return x * x;
}

template<typename T, typename U>
inline bool chmax(T &x, U y){
	if (x >= y) return false;
	x = y;
	return true;
}

template<typename T, typename U>
inline bool chmin(T &x, U y){
	if (x <= y) return false;
	x = y;
	return true;
}

template<typename T>
inline T& sort(T &c){
	sort(all(c));
	return c;
}

template<typename T>
inline T& reverse(T &c){
	reverse(all(c));
	return c;
}

template<typename T>
inline T& unique(T &c){
	sort(all(c));
	c.erase(unique(all(c)), end(c));
	return c;
}

template<typename T>
inline T sorted(const T &c){
	T d = c;
	return move(sort(d));
}

template<typename T>
inline T reversed(const T &c){
	T d = c;
	return move(reverse(d));
}

template<typename T>
inline T uniqued(const T &c){
	T d = c;
	return move(unique(d));
}

ll modpow(ll x, ll e, ll mod = 1000000007){
	ll res = 1;
	e %= mod - 1;
	while (e){
		if (e & 1) res = res * x;
		x = x * x;
		e >>= 1;
	}
	return res;
}

inline ll in(){
	ll x;
	scanf("%lld", &x);
	return x;
}

inline double inD(){
	double x;
	scanf("%lf", &x);
	return x;
}

inline string inS(){
	static char s[1024];
	scanf("%s", s);
	return s;
}

pair<ll, ll> rot45(ll x, ll y){
	return mp(x + y, x - y);
}

pair<ll, ll> rot45inv(ll u, ll v){
	return mp((u + v) / 2, (u - v) / 2);
}

template<typename T, size_t N>
struct print_tuple {
	static void print(const T &t, ostream &os){
		print_tuple<T, N - 1>::print(t, os);
		os << " " << get<N - 1>(t);
	}
};

template<typename T>
struct print_tuple<T, 1> {
	static void print(const T &t, ostream &os){
		os << get<0>(t);
	}
};

template<typename ...Args>
ostream& operator<<(ostream &os, const tuple<Args...> &t){
	print_tuple<tuple<Args...>, tuple_size<tuple<Args...>>::value>::print(t, os);
}
// }}}

int main()
{
	string s = inS();
	ll res = 0;
	rep(i, s.size()) rep(j, s.size()){
		swap(s[i], s[j]);
		chmax(res, stoi(s));
		swap(s[i], s[j]);
	}
	cout << res << endl;
}