using System;
using System.Linq;
using System.Collections.Generic;

namespace yukicoder
{
	class Programs
	{
		static void Main(string[] args)
		{
			int N = int.Parse(Console.ReadLine());
			var list = new List<int>();
			
			
			int tn = N;
			while(tn > 0)
			{
				list.Add(tn % 10);
				
				tn /= 10;
			}
			
			list.Reverse();
			
			for(int p = 0;p < list.Count - 1;p++)
			{
				int head = list[p];
				int max = -1;
				int maxIndex = -1;
				for(int q = p + 1;q < list.Count;q++)
				{
					int ch = list[q];
					if(max <= ch)
					{
						max = ch;
						maxIndex = q;
					}
					
				}
				
				if(max == -1 || max <= head)
				{
					continue;
				}else
				{
					list[p] = max;
					list[maxIndex] = head;
					break;
				}
			}
			list.Reverse();
			int sum = 0;
			int a = 1;
			foreach(int i in list)
			{
				sum += a * i;
				a *= 10;
			}
			Console.WriteLine(sum);
			
		}
		
	}
	
}