CIS 265 Summer 2015 Exam 1 First Name Last Name

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1 CIS 265 Summer 2015 Exam 1 First Name Last Name ID MULTIPLE CHOICE. (30pts - 3 pts each) Choose the one alternative that best completes the statement or answers the question. 1) Which of the following is the correct expression that evaluates to true if the number x is between 1 and 100 or the number is negative? A) 1 < x < 100 && x < 0 B) ((x < 100) && (x > 1)) (x < 0) C) (1 > x > 100) (x < 0) D) ((x < 100) && (x > 1)) && (x < 0) 1) 2) To check whether a char variable ch is an uppercase letter, you write. 2) A) (ch >= 'A' && ch <= 'Z') B) (ch >= 'A' && ch >= 'Z') C) ('A' <= ch <= 'Z') D) (ch >= 'A' ch <= 'Z') 3) What is i after the following for loop? 3) int y = 0; for (int i = 0; i<10; ++i) { y += i; A) 11 B) 10 C) 9 D) undefined 4) Given the following method 4) static void nprint(string message, int n) { while (n > 0) { System.out.print(message); n--; What is k after invoking nprint("a message", k)? int k = 2; nprint("a message", k); A) 1 B) 0 C) 2 D) 3 5) Analyze the following code: 5) System.out.println(xMethod(5, 500L)); public static int xmethod(int n, long l) { System.out.println("int, long"); return n; public static long xmethod(long n, long l) { System.out.println("long, long"); return n; A) The program displays long, long followed by 5. B) The program displays int, long followed by 5. C) The program runs fine but displays things other than 5. D) The program does not compile because the compiler cannot distinguish which xmethod to invoke.

2 6) Analyze the following code: 6) int[ ] x = new int[5]; int i; for (i = 0; i < x.length; i++) x[i] = i; System.out.println(x[i]); A) The program has a compile error because i is not defined in the last statement in the main method. B) The program has a runtime error because the last statement in the main method causes ArrayIndexOutOfBoundsException. C) The program displays D) The program displays 4. 7) Show the output of the following code: 7) int[ ] x = {1, 2, 3, 4, 5; increase(x); int[ ] y = {1, 2, 3, 4, 5; increase(y[0]); System.out.println(x[0] + " " + y[0]); public static void increase(int[ ] x) { for (int i = 0; i < x.length; i++) x[i]++; public static void increase(int y) { y++; A) 1 1 B) 1 2 C) 0 0 D) 2 2 E) 2 1 8) What is the output of the following code? 8) String s = "University"; s.replace("i", "ABC"); System.out.println(s); A) UnABCversity B) University C) UniversABCty D) UnABCversABCty 9) To check if a string s contains the prefix "Java", you may write (Choose all that apply.) 9) A) if (s.charat(0) == 'J' && s.charat(1) == 'a' && s.charat(2) == 'v' && s.charat(3) == 'a')... B) if (s.substring(0, 4).equals("Java"))... C) if (s.startswith("java"))... D) if (s.indexof("java") == 0)... E) All of the above.

3 10) What is the output of the following code? 10) String s1 = new String("Welcome to Java!"); String s2 = new String("Welcome to Java!"); if (s1.equals(s2)) System.out.println("s1 and s2 have the same contents"); else System.out.println("s1 and s2 have different contents"); A) s1 and s2 have different contents B) s1 and s2 have the same contents (20 points) Part 2. Java Programming Restriction: DO NOT USE Arrays.sort() or Collections.sort( ) methods. Alternative 1 Write a method to determine whether or not two strings are an anagram. Any two words or phrases that exactly include the same letters are called an anagram. For instance: dad and add, stressed and dessert, George Bush and He bugs Gore. Your method must not be case sensitive. The signature of the method follows: public static boolean isanagram (String s1, String s2) Alternative 2 Write a Java method to accept an ArrayList holding Integer numbers. It returns the total number of occurrences of the list s smallest value. For example, if the input list consists of {11, 22, 11, 33, 55, 77, 44, 11, 88, 11, the requested method should: identify 11 as the minimum, count repetitions, and return the value 4. Your solution should work for any list of integers (not just the sample given here) public static int countoccurrencesofsmallest ( ArrayList<Integer> list ) Alternative 3 This problem is based on the GeometricObject Rectangle Circle classes discussed in class, see diagram. Assume you are given an ArrayList holding various Rectangle objects. Write a method to be added to the Driver class to determine whether there are rectangles in the list having the same area and color. The method returns true if such duplicate rectangles are found, false otherwise. The method s signature is given below. public static int hasduplicaterectangleswithsameareaandcolor(arraylist list)

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7 1) B 2) A 3) D 4) C 5) B 6) B 7) E 8) B 9) E 10) B