import java.util.*;
 

public class Main {
	
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n= sc.nextInt();
		String num = n+"";
		for(int i=0;i<num.length()-1;i++){
			int max=num.charAt(i);
			int basyo=i;
			for(int j=i+1;j<num.length();j++){
				if(max<=num.charAt(j)&num.charAt(j)!=num.charAt(i)){
					basyo=j;
					max=num.charAt(j);
				}
			}
			if(basyo!=i){
				char[] sss = num.toCharArray();
				char temp = sss[i];
				sss[i]=sss[basyo];
				sss[basyo]=temp;
				String ans="";
				for(int k=0;k<num.length();k++){
					ans+=sss[k];
				}
				System.out.println(ans);
				return;
			}
			
		}
		System.out.println(n);

	}
}