EBK BUSINESS DRIVEN TECHNOLOGY
7th Edition
ISBN: 8220103675451
Author: BALTZAN
Publisher: YUZU
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Chapter 11, Problem 4CQ
Program Plan Intro
Zappos:
- Zappos is one of the online marketing services that sell more than 500 brands of clothing, handbags, and accessories.
- Zappos mainly dependent on their customers and encourages them to order many products and it also provides customization.
- The call center of Zappos receives many calls in a day dealing with their customers.
Amazon:
- The purpose of this site is to deliver products to their customers. It is a giant market where customer can find various products.
- They sell products like books, household items, electronic gadgets, etc.
- Its mission is to be customer centric and providing online shopping.
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Students have asked these similar questions
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 11 Solutions
EBK BUSINESS DRIVEN TECHNOLOGY
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