Swap both values
if ( smallGreatDgt != - 1 ) { str = swap ( str , index , smallGreatDgt ) ; return str ; } return " - 1" ; } static String swap ( String str , int i , int j ) { char ch [ ] = str . toCharArray ( ) ; char temp = ch [ i ] ; ch [ i ] = ch [ j ] ; ch [ j ] = temp ; return String . valueOf ( ch ) ; }