EXPRESSION TREE

EXPRESSION TREE

Aim:

                                    To write a C program to demonstrate an expression tree.

Algorithm for Main ()

                                    Step 1: [ INCLUDE NECESSARY HEADER FILES]

                                    Step 2: [READ X]

                                    Step 3:[ CALL EXPTREE(),CALL DISPLAY(), CALL INORDER(),CALL

 PREORDER(),CALL EVALUATE ()]

Algorithm for EXPTREE()

            Step 1: Read Character

            Step 2: IF Character        operator then

                        CALL PUSH_OP()

            Step 3: [IF Character has only numbers]

                        IF [ is ALnum( str[i]           1 )] THEN

                        CREATE Newnode

            Step 4: Check for ‘ NULL ‘ condition

            Step 5: ASSIGN priority

            Step 6: IF ( Priority !=0) THEN CALL POP_OP()

            Step 7: IF Character = ‘)’ THEN CALL PUSH_OP()

Algorithm for INORDER (tree t)

            Step 1: IF (t!=NULL) THEN

                        CALL INORDER(t         left)

            Step 2: PRINT t         element

            Step 3: CALL INORDER(t          right)

Algorithm for PREORDER (tree t)

            Step 1: IF (t!=NULL) THEN

                        PRINT t         element

            Step 2: CALL PREORDER(t         left)

            Step 3: CALL INORDER(t          right)

Algorithm for POSTORDER(tree t)

            Step 1: IF (t!=NULL) THEN

                        CALL POSTORDER(t         left)

                        CALL POSTORDER(t          right)

Step 2: PRINT t         element