Starting Out with Java: From Control Structures through Objects (7th Edition) (What's New in Computer Science)
7th Edition
ISBN: 9780134802213
Author: Tony Gaddis
Publisher: PEARSON
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Textbook Question
Chapter 8, Problem 9MC
The Java Virtual Machine periodically performs this process, which automatically removes unreferenced objects from memory.
- a. memory cleansing
- b. memory deallocation
- c. garbage collection
- d. object expungement
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4. Suppose we have a perfect binary tree with height h 0 representing a heap, meaning it
=
has n 2+1 1 keys indexed from 1 to 2+1 1. When we run convertomaxheap we run
maxheapify in reverse order on every key with children.
Let's examine the worst-case - In the worst-case every single key gets swapped all the way to
the leaf level.
(a) For each level in the tree there are a certain number of nodes and each of those nodes [10 pts]
requires a certain number of swaps. Fill in the appropriate values/expressions in the
table:
Level
Number of Keys
Number of Swaps per Key
0
2
..
(b) Write down a sum for the total number of swaps required. This should involve h, not n.
[10 pts]
Total
The next problem concerns the following C code:
/copy input string x to buf */
void foo (char *x) {
char buf [8];
strcpy((char *) buf, x);
}
void callfoo() {
}
foo("ZYXWVUTSRQPONMLKJIHGFEDCBA");
Here is the corresponding machine code on a Linux/x86 machine:
0000000000400530 :
400530:
48 83 ec 18
sub
$0x18,%rsp
400534:
48 89 fe
mov
%rdi, %rsi
400537:
48 89 e7
mov
%rsp,%rdi
40053a:
e8 di fe ff ff
callq
400410
40053f:
48 83 c4 18
add
$0x18,%rsp
400543:
c3
retq
400544:
0000000000400544 :
48 83 ec 08
sub
$0x8,%rsp
400548:
bf 00 06 40 00
mov
$0x400600,%edi
40054d:
e8 de ff ff ff
callq 400530
400552:
48 83 c4 08
add
$0x8,%rsp
400556:
c3
This problem tests your understanding of the program stack. Here are some notes to
help you work the problem:
⚫ strcpy(char *dst, char *src) copies the string at address src (including
the terminating '\0' character) to address dst. It does not check the size of
the destination buffer.
• You will need to know the hex values of the following characters:
1234
3. Which line prevents compiler optimization? Circle one: 1234
Suggested solution:
Store strlen(str) in a variable before the if statement.
⚫ Remove the if statement.
Replace index 0 && index < strlen(str)) {
5 }
}
=
str [index] = val;
Chapter 8 Solutions
Starting Out with Java: From Control Structures through Objects (7th Edition) (What's New in Computer Science)
Ch. 8.1 - What is the difference between an instance field...Ch. 8.1 - Prob. 8.2CPCh. 8.1 - Describe the limitation of static methods.Ch. 8.8 - Prob. 8.4CPCh. 8.9 - Look at the following statement, which declares an...Ch. 8.9 - Assume that the following enumerated data type has...Ch. 8.9 - Prob. 8.7CPCh. 8 - This type of method cannot access any non-static...Ch. 8 - Prob. 2MCCh. 8 - If you write this method for a class, Java will...
Ch. 8 - Making an instance of one class a field in another...Ch. 8 - This is the name of a reference variable that is...Ch. 8 - This enum method returns the position of an enum...Ch. 8 - Assuming the following declaration exists: enum...Ch. 8 - You cannot use the fully qualified name of an enum...Ch. 8 - The Java Virtual Machine periodically performs...Ch. 8 - If a class has this method, it is called...Ch. 8 - CRC stands for a. Class, Return value, Composition...Ch. 8 - True or False: A static member method may refer to...Ch. 8 - True or False: All static member variables are...Ch. 8 - Prob. 14TFCh. 8 - Prob. 15TFCh. 8 - Prob. 16TFCh. 8 - True or False: Enumerated data types are actually...Ch. 8 - True or False: enum constants have a toString...Ch. 8 - public class MyClass { private int x; private...Ch. 8 - Assume the following declaration exists : enum...Ch. 8 - Consider the following class declaration: public...Ch. 8 - Consider the following class declaration: public...Ch. 8 - A pet store sells dogs, cats, birds, and hamsters....Ch. 8 - Prob. 1SACh. 8 - Prob. 2SACh. 8 - Prob. 3SACh. 8 - Even if you do not write an equals method for a...Ch. 8 - A has a relationship can exist between classes....Ch. 8 - Prob. 6SACh. 8 - Is it advisable or not advisable to write a method...Ch. 8 - Prob. 8SACh. 8 - Look at the following declaration: enum Color {...Ch. 8 - Assuming the following enum declaration exists:...Ch. 8 - Under what circumstances does an object become a...Ch. 8 - Area Class Write a class that has three overloaded...Ch. 8 - BankAccount Class Copy Constructor Add a copy...Ch. 8 - Carpet Calculator The Westfield Carpet Company has...Ch. 8 - LandTract Class Make a LandTract class that has...Ch. 8 - Month Class Write a class named Month. The class...Ch. 8 - CashRegister Class Write a CashRegister class that...Ch. 8 - Sales Receipt File Modify the program you wrote in...Ch. 8 - Parking Ticket Simulator For this assignment you...Ch. 8 - Geometry Calculator Design a Geometry class with...Ch. 8 - Car Instrument Simulator For this assignment, you...Ch. 8 - First to One Game This game is meant for two or...Ch. 8 - Heads or TaiLs Game This game is meant for two or...
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