5.19 LAB: Word Frequencies  Write a program that reads a list of words. Then, the program outputs those words and their frequencies. The input begins with an integer indicating the number of words that follow. Assume that the list will always contain fewer than 20 words. Hint: Use two vectors, one for the strings and one vector for the frequencies. Please write in C++

Write a program that reads in a line consisting of a students name, Social Security number, user ID, and password. The program outputs the string in which all the digits of the Social Security number and all the characters in the password are replaced by x. (The Social Security number is in the form 000-00-0000, and the user ID and the password do not contain any spaces.) Your program should not use the operator [] to access a string element. Use the appropriate functions described in Table 7-1.

(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

(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.

(Electrical eng.) Write a program that specifies three one-dimensional arrays named current, resistance, and volts. Each array should be capable of holding 10 elements. Using a for loop, input values for the current and resistance arrays. The entries in the volts array should be the product of the corresponding values in the current and resistance arrays (sovolts[i]=current[i]resistance[i]). After all the data has been entered, display the following output, with the appropriate value under each column heading: CurrentResistance Volts

(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?

(File creation) Write a C++ program that creates an array containing the integer numbers 60, 40, 80, 90, 120, 150, 130, 160, 170, and 200. Your program should then write the data in the array to a text file. (Alternatively, you can create the file with a text editor.)

(List maintenance) a. Write a complete C++ program that can be used to update an ordered list of numbers. Use the list of numbers shown in Figure 7.13 to test that your program is working correctly. b. Test the program you wrote for Exercise 4a, using a new part number of 86 with the list of numbers shown in Figure 7.13. This test should place this new code at the beginning of the existing list. c. Test the program you wrote for Exercise 4a, using a part number of 200 with the list of numbers shown in Figure 7.13. This test should place this new part number at the end of the existing list

(Conversion) a. Write a C++ program to convert meters to feet. The program should request the starting meter value, the number of conversions to be made, and the increment between metric values. The display should have appropriate headings and list the meters and the corresponding feet value. If the number of iterations is greater than 10, have your program substitute a default increment of 10. Use the relationship that 1 meter = 3.281 feet. b. Run the program written in Exercise 6a on a computer. Verify that your program begins at the correct starting meter value and contains the exact number of conversions specified in your input data. c. Modify the program written in Exercise 6a to request the starting meter value, the ending meter value, and the increment. Instead of the condition checking for a fixed count, the condition checks for the ending meter value. If the number of iterations is greater than 20, have your program substitute a default increment of (ending value - starting value) / 19.

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)