Infix:  (A+B);
Postfix:  AB+
Infix:  ((A+B)-(C+D));
Postfix:  AB+CD+-
Infix:  A+B-C;
Postfix:  AB+C-
Infix:  A*B/C;
Postfix:  AB*C/
Infix:  A+B*C;
Postfix:  ABC*+
Infix:  A-B*C;
Postfix:  ABC*-
Infix:  A*B-C;
Postfix:  AB*C-
Infix:  (A*B)*(D-E+F)/((G+H)*(I-J)).
Postfix:  AB*DE-F+*GH+IJ-*/