import java.util.Scanner;


public class Main_yukicoder39 {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        char[] n = sc.next().toCharArray();

        int max = Integer.parseInt(new String(n));
        for (int i = 0; i < n.length; i++) {
        	for (int j = i + 1; j < n.length; j++) {
        		char tmp = n[i];
        		n[i] = n[j];
        		n[j] = tmp;
        		max = Math.max(max, Integer.parseInt(new String(n)));
        		 tmp = n[i];
        		n[i] = n[j];
        		n[j] = tmp;
        	}
        }

        System.out.println(max);
        
        sc.close();
    }
}