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

int main()
{
int i;
int iLen;
int iPos;
int iPos2;
char S[ 12 ];
char T[ 12 ];
char C;
char cMax;

	cin >> S;

	iLen = strlen( S );
	strcpy( T, S );
	
	sort( T, T + iLen, greater<char>() );

	for( i = 0; i < iLen; i++ )
	{
		if( T[ i ] != S[ i ] )
		{
			iPos = i;
			C = T[ i ];

			break;
		}
	}

	if( i == iLen )
	{
		cout << S << endl;

		return 0;
	}

	for( i = iLen - 1; i > iPos; i-- )
	{
		if( C == S[ i ] )
		{
			swap( S[ i ], S[ iPos ] );

			break;
		}
	}

	cout << S << endl;

	return 0;
}