ISRO2017-50
If the post order traversal gives ab -cd * + then the label of the nodes 1,2,3.. will be + , -, *, a,b,c,d a, -,b,+,c,*,d a,b,c,d,-,*,+ -,a,b,+,*,c,d
If the post order traversal gives ab -cd * + then the label of the nodes 1,2,3.. will be+ , -, *, a,b,c,da, -,b,+,c,*,da,b,c,d,-,*,+-,a,b,+,*,c,d