Q1: Create a function int evaluatePostfix(const string& expr) that uses StackDLL to evaluate the mathematical expression is postfix(the operator after the 2 operands) Examples: evaluatePostfix("35+") returns 8 evaluatePostfix("32*31*/") returns 2 evaluatePostfix("51-21++") returns 7 test your function in the main driver

(Statistics) a. Write a C++ program that reads a list of double-precision grades from the keyboard into an array named grade. The grades are to be counted as they’re read, and entry is to be terminated when a negative value has been entered. After all grades have been input, your program should find and display the sum and average of the grades. The grades should then be listed with an asterisk (*) placed in front of each grade that’s below the average. b. Extend the program written for Exercise 1a to display each grade and its letter equivalent, using the following scale: Between90and100=AGreaterthanorequalto80andlessthan90=BGreaterthanorequalto70andlessthan80=CGreaterthanorequalto60andlessthan70=DLessthan60=F

(List maintenance) The following letters are stored in an alphabet array: B, J, K, M, S, and Z. Write and test a function named adlet(), which accepts the alphabet array and a new letter as arguments, and then inserts the new letter in the correct alphabetical order in the array.

(Numerical) a. The following is an extremely useful programming algorithm for rounding a real number to n decimal places: Step 1: Multiply the number by 10n Step 2: Add 0.5 Step 3: Delete the fractional part of the result Step 4: Divide by 10n For example, using this algorithm to round the number 78.374625 to three decimal places yields: Step1:78.374625103=78374.625 Step2:78374.625+0.5=78375.125 Step3:Retainingtheintegerpart=78375Step4:78375dividedby103=78.375 Using this algorithm, write a C++ function that accepts a user-entered value and returns the result rounded to two decimal places. b. Enter, compile, and run the program written for Exercise 11a.

Mark the following statements as true or false. A double type is an example of a simple data type. (1) A one-dimensional array is an example of a structured data type. (1) The size of an array is determined at compile time. (1,6) Given the declaration: int list[10]; the statement: list[5] - list[3] * list[2]; updates the content of the fifth component of the array list. (2) If an array index goes out of bounds, the program always terminates in an error. (3) The only aggregate operations allowable on int arrays are the increment and decrement operations. (5) Arrays can be passed as parameters to a function either by value or by reference. (6) A function can return a value of type array. (6) In C++, some aggregate operations are allowed for strings. (11,12,13) The declaration: char name [16] = "John K. Miller"; declares name to be an array of 15 characters because the string "John K. Miller" has only 14 characters. (11) The declaration: char str = "Sunny Day"; declares str to be a string of an unspecified length. (11) As parameters, two-dimensional arrays are passed either by value or by reference. (15,16)

Mark the following statements as true or false: a. To use a predefined function in a program, you need to know only the name of the function and how to use it. (1) b. A value-returning function returns only one value. (2, 3) c. Parameters allow you to use different values each time the function is called. (2, 7, 9) d. When a return statement executes in a user-defined function, the function immediately exits. (3, 4) e. A value-returning function returns only integer values. (4) f. A variable name cannot be passed to a value parameter. (3, 6) g. If a C++ function does not use parameters, parentheses around the empty parameter list are still required. (2, 3, 6) h. In C + + , the names of the corresponding formal and actual parameters must be the same. (3, 4, 6) i. A function that changes the value of a reference parameter also changes the value of the actual parameter. (7) j. Whenever the value of a reference parameter changes, the value of the actual parameter changes. (7) k. In C++, function definitions can be nested; that is, the definition of one function can be enclosed in the body of another function. (9) l. Using global variables in a program is a better programming style than using local variables, because extra variables can be avoided. (10) m. In a program, global constants are as dangerous as global variables. (10) n. The memory for a static variable remains allocated between function calls. (11)

(Electrical eng.) a. An engineer has constructed a two-dimensional array of real numbers with three rows and five columns. This array currently contains test voltages of an amplifier. Write a C++ program that interactively inputs 15 array values, and then determines the total number of voltages in these ranges: less than 60, greater than or equal to 60 and less than 70, greater than or equal to 70 and less than 80, greater than or equal to 80 and less than 90, and greater than or equal to 90. b. Entering 15 voltages each time the program written for Exercise 7a runs is cumbersome. What method could be used for initializing the array during the testing phase? c. How might the program you wrote for Exercise 7a be modified to include the case of no voltage being present? That is, what voltage could be used to indicate an invalid voltage, and how would your program have to be modified to exclude counting such a voltage?

(Data processing) A bank’s customer records are to be stored in a file and read into a set of arrays so that a customer’s record can be accessed randomly by account number. Create the file by entering five customer records, with each record consisting of an integer account number (starting with account number 1000), a first name (maximum of 10 characters), a last name (maximum of 15 characters), and a double-precision number for the account balance. After the file is created, write a C++ program that requests a user-input account number and displays the corresponding name and account balance from the file.

(Program) Include the Date class definition in Class 11.1 in a complete program. Your program should verify that each member function works correctly.

(Numerical) a. Define an array with a maximum of 20 integer values, and fill the array with numbers input from the keyboard or assigned by the program. Then write a function named split() that reads the array and places all zeros or positive numbers in an array named positive and all negative numbers in an array named negative. Finally, have your program call a function that displays the values in both the positive and negative arrays. b. Extend the program written for Exercise 6a to sort the positive and negative arrays into ascending order before they’re displayed.