#include <algorithm>
#include <cstdio>
#include <iostream>
#include <map>
#include <math.h>
#include <queue>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <vector>
using namespace std;

#define ll long long
#define INF (1 << 30)
#define INFLL (1LL << 60)

int toInt(string str){
	int ret;
	stringstream ss;
	ss << str;
	ss >> ret;
	return ret;
}

int main() {
	string str;
	int ans = 0;
	cin >> str;
	ans = toInt(str);

	for(int i = 0;i < str.size();i++){
		for(int j = 0;j < str.size();j++){
			if(i == j) continue;
			string cp = str;
			swap(cp[i], cp[j]);
			int now = toInt(cp);
			ans = max(ans, now);
		}
	}

	cout << ans << endl;
	return 0;
}