Starting Out with C++ from Control Structures to Objects (9th Edition)
9th Edition
ISBN: 9780134498379
Author: Tony Gaddis
Publisher: PEARSON
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Textbook Question
Chapter 12, Problem 52RQE
T F ifstream objects, by default, create a file if it doesn’t exist when opened.
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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 12 Solutions
Starting Out with C++ from Control Structures to Objects (9th Edition)
Ch. 12.1 - Which file access flag would you use if you want...Ch. 12.1 - Prob. 12.2CPCh. 12.1 - Assuming diskInfo is an fstream object, write a...Ch. 12.1 - Assuming diskInfo is an fstream object, write a...Ch. 12.1 - Assuming diskInfo is an fstream object, write a...Ch. 12.1 - Write a statement that defines an fstream object...Ch. 12.5 - Assume the file input.txt contains the following...Ch. 12.5 - Describe the difference between reading a file...Ch. 12.5 - What will be stored in the file out.txt after the...Ch. 12.10 - Describe the difference between the seekg and the...
Ch. 12.10 - Describe the difference between the tellg and the...Ch. 12.10 - Describe the meaning of the following file access...Ch. 12.10 - What is the number of the first byte in a file?Ch. 12.10 - Briefly describe what each of the following...Ch. 12.10 - Describe the mode that each of the following...Ch. 12 - What capability does the fstream data type provide...Ch. 12 - Which file access flag do you use to open a file...Ch. 12 - Assume the file data.txt already exists, and the...Ch. 12 - How do you combine multiple file access flags when...Ch. 12 - Should file stream objects be passed to functions...Ch. 12 - Under what circumstances is a file stream objects...Ch. 12 - Under what circumstances is a file stream objects...Ch. 12 - Under what circumstances is a file stream objects...Ch. 12 - How do you read the contents of a text file that...Ch. 12 - What arguments do you pass to a file stream...Ch. 12 - What arguments do you pass to a file stream...Ch. 12 - Prob. 12RQECh. 12 - Prob. 13RQECh. 12 - How do you get the byte number of a files current...Ch. 12 - If a program has read to the end of a file, what...Ch. 12 - How do you determine the number of bytes that a...Ch. 12 - How do you rewind a sequential-access file?Ch. 12 - The _____ file stream data type is for output...Ch. 12 - If a file fails to open, the file stream object...Ch. 12 - The same formatting techniques used with...Ch. 12 - The _____ function reads a line of text from a...Ch. 12 - The ____________ member function reads a single...Ch. 12 - The ________member function writes a single...Ch. 12 - Prob. 24RQECh. 12 - __________ files contain data formatted as...Ch. 12 - Prob. 26RQECh. 12 - Prob. 27RQECh. 12 - The ___________ member function writes raw binary...Ch. 12 - The __________ member function reads raw binary...Ch. 12 - Prob. 30RQECh. 12 - In ___________ file access, the contents of the...Ch. 12 - In __________ file access, the contents of a file...Ch. 12 - The _____________ member function moves a files...Ch. 12 - The ___________ member function moves a files...Ch. 12 - The __________ member function returns a files...Ch. 12 - The ___________ member function returns a files...Ch. 12 - The __________ mode flag causes an offset to be...Ch. 12 - The __________ mode flag causes an offset to be...Ch. 12 - The ________ mode flag causes an offset to be...Ch. 12 - A negative offset causes the files read or write...Ch. 12 - Write a statement that defines a file stream...Ch. 12 - Write two statements that use a file stream object...Ch. 12 - Write two statements that use a file stream object...Ch. 12 - Write two statements that use a file stream object...Ch. 12 - Write a program segment that defines a file stream...Ch. 12 - Write code that opens the file data.txt for both...Ch. 12 - Write code that determines the number of bytes...Ch. 12 - The infoFile file stream object is used to...Ch. 12 - T F Different operating systems have different...Ch. 12 - T F fstream objects are only capable of performing...Ch. 12 - T F ofstream objects, by default, delete the...Ch. 12 - T F ifstream objects, by default, create a file if...Ch. 12 - T F Several file access flags may be joined by...Ch. 12 - T F A file may be opened in the definition of the...Ch. 12 - T F If a file is opened in the definition of the...Ch. 12 - T F A file stream objects fail member function may...Ch. 12 - T F The same output formatting techniques used...Ch. 12 - T F The operator expects data to be delimited by...Ch. 12 - T F The getline member function can be used to...Ch. 12 - T F It is not possible to have more than one file...Ch. 12 - T F Binary files contain unformatted data, not...Ch. 12 - T F Binary is the default mode in which files are...Ch. 12 - T F The tellp member function tells a file stream...Ch. 12 - T F It is possible to open a file for both input...Ch. 12 - fstream file(ios::in | ios::out);...Ch. 12 - ofstream file; file.open (info.dat, ios::tin); if...Ch. 12 - fstream file("info.dat"); if (!file) { cout ...Ch. 12 - fstream dataFile("info.dat", ios:in | ios:binary);...Ch. 12 - Prob. 69RQECh. 12 - fstream dataFi1e("info.dat", ios:in); char...Ch. 12 - Prob. 71RQECh. 12 - fstream inFile("info.dat", ios:in); int x;...Ch. 12 - File Head Program Write a program that asks the...Ch. 12 - File Display Program Write a program that asks the...Ch. 12 - Punch Line Write a program that reads and prints a...Ch. 12 - Tail Program Write a program that asks the user...Ch. 12 - Line Numbers (This assignment could be done as a...Ch. 12 - String Search Write a program that asks the user...Ch. 12 - Sentence Filter Write a program that asks the user...Ch. 12 - Array/File Functions Write a function named...Ch. 12 - File Encryption Filter File encryption is the...Ch. 12 - File Decryption Filter Write a program that...Ch. 12 - Prob. 11PCCh. 12 - Prob. 12PCCh. 12 - Inventory Program Write a program that uses a...Ch. 12 - Inventory Screen Report Write a program that reads...Ch. 12 - Average Number of Words If you have downloaded...Ch. 12 - Customer Accounts This program should be designed...
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