Alter the program such that only the correct output is sent to the standard output stream (stdout), while error and help messages are sent to the standard error stream (stderr). (Hint: use fprintf.) See the expected output listed in the comment at the top of main. c for an example of what should go to stdout.

Consider the usual algorithm to convert an infix expression to a postfix expression. suppose that you have read 10 input characters during a conversion and that the stack now contains these symbols: (5 points) | | | + | | ( | bottom |_*_| now, suppose that you read and process the 11th symbol of the input. draw the stack for the case where the 11th symbol is