Driver code
public static void main ( String [ ] args ) { char [ ] in = { ' D ' , ' B ' , ' E ' , ' A ' , ' F ' , ' C ' } ; char [ ] pre = { ' A ' , ' B ' , ' D ' , ' E ' , ' C ' , ' F ' } ; int len = in . length ; Tree . root = buldTreeWrap ( in , pre , len ) ;