question: private Deque < Character > dequeFrom ( CharSequence in ) { if ( in == null ) { return null ; } final Deque < Character > out = new ArrayDeque < > ( in . length ( ) ) ; for ( int i = in . length ( ) - 1 ; i >= 0 ; i -- ) { out . push ( in . charAt ( i ) ) ; } return out ; }
target:  Creates deque (double-side queue) of CharSequence