1. [3 pts] What is your section number, the period your discussion meets, and the name of your discussion leader?

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1 CIS 3022 Prog for CIS Majors I February 10, 2009 Exam I Print Your Name Your Section # Total Score Your work is to be done individually. The exam is worth 105 points (five points of extra credit are available throughout the exam) and it has 17 questions. If you notice an error in any portions of the Java code provided within a question, mark through and correct the error. Unless a question directly instructs you to correct a portion of code, there are no known errors. There are times when errors within a portion of code are unnoticed. We will consider giving extra credit for any errors corrected. However, be aware there must actually be an error in the code (programming conventions do not apply). Be sure of yourself, inaccurate corrections could cause you to lose points. 1. [3 pts] What is your section number, the period your discussion meets, and the name of your discussion leader? 2. [3 pts] Describe a compiler. Compiler - compile for a targeted HW/SW - create binary set instructions - create a separate file, executable file - often this process will create a faster executing solution 3. [4 pts] Fill in the bit size of each type listed. Type # of Bits Type # of Bits int _32_ float _32_ byte _8_ char _16_ 4. [2 pts] Our usage of Java requires both the Development Kit and the Runtime Environment. True OR False (Both are correct) 5. [3 pts] The class GroundHog has been created and placed in the file February.java. Show how to compile GroundHog. javac February.java 6. [3 pts] What is the name of the file created after GroundHog has been compiled (include any file extension)? GroundHog.class 7. [3 pts] Show how to run the program compiled in Question 5. java GroundHog

2 February 10, 2008 CIS 3022 Exam I Page 2 of 6 Score 8. [18 pts] Given this sample computer system, fill in the appropriate portions of each table. The system has a 5-bit program counter, an 8-bit Accumulator, and 32 bytes of addressable memory (we will only use a portion of the memory). The system utilizes the instruction set and initial memory shown here. Instruction Set Memory OPCODE MNEMONIC ADDRESS ORIGINAL NEW CONTENTS CONTENTS 000 HALT STAM LDAM LDAI ADDM ADDI SUBM SUBI Given this structure and starting at 00000, step through and show the execution of the system by filling in the all of the fields within the table below. If there are any changes to the 8 bytes of memory, show what they are here by placing the new contents in the NEW CONTENTS column above, next to the original contents. If the position does not change you do not need to place anything in the NEW CONTENTS column. PC Accumulator (before instruction) Instruction Psuedo Code Accumulator (after instruction) Gabage or????? LDAI 13 A := ADDM 0 A := A + M[00000] STAM 8 M[01000] := A LDAM 9 A := M[01001] SUBM 7 A := A M[00111] STAM 1 M[00001] := A HALT -

3 February 10, 2008 CIS 3022 Exam I Page 3 of 6 Score 9. [12 pts] What is the value of d after each statement executes? Also, what are the values of a, b, and c after all of the statements have executed? Note that the statements are sequential, the first possibly affecting the second, possibly affecting the third, and so on. int a = 3, b = 3, c = 10, d = 4; d += c / ++b + 3 * a; d = b % a * 4 ++c; d = c ++a % b + 2; All executions complete: d = _15_ d = -11_ d = _12_ a = _4 b = _3 c = _11_ 10. [6 pts] Given the variables x and y as well as their declarations, to what value do the following expressions evaluate? int x = 18, y = 7;!(x == 8 y!= x) Evaluation = false (x!= y + 3 && y % x < 5) Evaluation = false (y == x && y!= x) Evaluation = false 11. [4 pts] Declare a variable of the type created by the expressions in the previous question. Assign the variable the result of the expression:!(x == 8 y!= x). Then use one print statement to print to the console (command prompt) the name of your new variable. In another print statement, print an equals sign and the value of your newly declared variable. Have both print statements display on the same line in the console. boolean result =! (x == 8 y!= x); System.out.print( result ); System.out.println( = + result);

4 February 10, 2008 CIS 3022 Exam I Page 4 of 6 Score 12. [8 pts] Step through this series of statements and show the output produced. Also, state the final value of x and y after all the statements have executed. int x = 7, y = 4; if (x / y == 1) { y = x + 2; System.out.println( First ); if (y % x == 4) { y = --x * 2; System.out.println( Second ); else if (y % x == 2) { y = x++ / 2; System.out.println( Third ); else { x = x / 2; y = y + 2; System.out.println( Fourth ); Output First Third Final Values x = _8 y = _3 13. [6 pts] Using the variables declared here, either re-write on the right hand side these three lines of code using a cast if it is necessary or write none if no casting is needed. Note the statements are sequential, the second and third needing the variable declared in the first. Code: float value = 28.61; byte bits = value; int result = bits; Re-written Code or None: float value = (float)28.61; byte bits = (byte)value; None 14. [3 pts] Selecting the appropriate type, create your own variable and using a pre-defined Java method initialize your variable to the rounded value of the float value declared in the previous question. int number = Math.round(value); 15. [3 pts] Using a pre-defined Java method, calculate and print to the screen the result of 8 raised to the power 3. System.out.println(Math.pow(8,3));

5 February 10, 2008 CIS 3022 Exam I Page 5 of 6 Score 16. [10 pts] Create a class CharacterComparison. The class will contain the main method. The program will allow the user to enter two char values. Upon receiving the two char values, place them within Character objects. Compare the Characters, printing to the screen the difference between them. class CharacterComparison { public static void main(string args[]) { Scanner sc = new Scanner(System.In); char c1, c2; String s1, s2; System.out.println( Please enter the first character: ); s1=sc.next(); c1=s1.charat(0); Character a = new Character(c1); System.out.println( Please enter the second character: ); s2=sc.next(); c2=s2.charat(0); Character b = new Character(c2); System.out.println( The difference between the two characters is: + a.compareto(b);

6 February 10, 2008 CIS 3022 Exam I Page 6 of 6 Score 17. [14 pts] Create a class StringOperations. The class will contain the main method. First, request and receive an initial String value from the user. Then, ask the user to make a selection between three menu options: substring, concatenation, and length. Ask the user for any additional information, based upon the selection made, i.e. for substring receive the beginning and ending indexes of the substring desired and for concatenation receive the additional String to concatenate to the original String entered. The length operation will not require any additional information to determine the length of the String entered. Finally, print to the screen the result obtained from the option selection. import java.util.scanner; class StringOperations { public static void main(string args[]) { Scanner scanner = new Scanner(System.in); System.out.print("Enter a string: "); String initial = scanner.next(); System.out.println("1. Substring"); System.out.println("2. Concatenation"); System.out.println("3. Length"); System.out.print("Enter a selection (1-3): "); int selection = scanner.nextint(); if (selection == 1) { System.out.print("Enter the beginning index: "); int begin = scanner.nextint(); System.out.print("Enter the ending index: "); int end = scanner.nextint(); System.out.println("Substring: " + initial.substring(begin, end)); else if (selection == 2) { System.out.print("Enter a second string: "); String second = scanner.next(); System.out.println("Concatenation: " + initial.concat(second)); else if (selection == 3) { System.out.println("Length: " + initial.length()); else { System.out.println("That was not a valid choice.");