static void find ( int n ) {
  String [ ] arr = new String [ n + 1 ] ;
  arr [ 0 ] = "" ;
  int size = 1 , m = 1 ;
  while ( size <= n ) {
    for ( int i = 0 ;
    i < m && ( size + i ) <= n ;
    i ++ ) arr [ size + i ] = "3" + arr [ size - m + i ] ;
    for ( int i = 0 ;
    i < m && ( size + m + i ) <= n ;
    i ++ ) arr [ size + m + i ] = "4" + arr [ size - m + i ] ;
    m = m << 1 ;
    size = size + m ;
  }
  System . out . println ( arr [ n ] ) ;
}

static void find ( int n ) { String [ ] arr = new String [ n + 1 ] ; arr [ 0 ] = " " ; int size = 1 , m = 1 ; while ( size <= n ) { for ( int i = 0 ; i < m && ( size + i ) <= n ; i ++ ) arr [ size + i ] = "3" + arr [ size - m + i ] ; for ( int i = 0 ; i < m && ( size + m + i ) <= n ; i ++ ) arr [ size + m + i ] = "4" + arr [ size - m + i ] ; m = m << 1 ; size = size + m ; } System . out . println ( arr [ n ] ) ; }
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