print root node at the end of traversal
System . out . print ( in [ inIndex ] + " ▁ " ) ; } void printPostMain ( int [ ] in , int [ ] pre ) { int n = pre . length ; HashMap < Integer , Integer > hm = new HashMap < Integer , Integer > ( ) ; for ( int i = 0 ; i < n ; i ++ ) hm . put ( in [ i ] , i ) ; printPost ( in , pre , 0 , n - 1 , hm ) ; }