Test 1: Constructor and build function

Test 2: Postorder traversal

Original expression string: 3.5 2.7 + -4.7 2.64 * -
Postorder traversal of t1:  3.5 2.7 + -4.7 2.64 * - 

Test 3: Evaluate tree

Value of expression represented by t1 = 18.608

Test 4: Inorder traversal

Inorder traversal of t1: ( ( ( 3.5 ) + ( 2.7 ) ) - ( ( -4.7 ) * ( 2.64 ) ) ) 

Test 5: Level-by-level traversal

Level-by-level traversal of t1: - + * 3.5 2.7 -4.7 2.64 
Test 6: Copy constructor

Postorder traversal of t2: 3.5 2.7 + -4.7 2.64 * - 

Test 7: Clear t2

Level-by-level traversal of t2: 
Test 8: Build new tree with variables

Original expression string: A 47.2 + B - 36 C / *
Postorder traversal of t2:  A 47.2 + B - 36 C / * 

Test 9: Printing variables of t2

A 10 B 25 C 2 

Value of expression represented by t2 = 579.6

Test 10: Assignment operator

Postorder traversal of t3:  A 47.2 + B - 36 C / * 

Test 11: Evaluate tree containing variables

Value of expression represented by t3 = 579.6

Test 12: Set existing variables to new values

Printing variables of t3

A 8 B 25 C 3 

Value of expression represented by t3 = 362.4