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•?Public-key cryptography is also known as asymmetric-key cryptography.
•?Encryption and decryption is carried out using two different keys. The two keys in such a key pair are referred to as the public key and the private key. (As we will see, this solves one of the most vexing problems associated with symmetric-key cryptography — the problem of key distribution).
•?With public key cryptography, all parties interested in secure communications can publish their public keys
lydiajane74 answered the question on May 13, 2018 at 23:26
- What is a certificate and why are certificates needed in public key cryptography?(Solved)
What is a certificate and why are certificates needed in public key cryptography?
Date posted: May 13, 2018. Answers (1)
- Given this class fragment,
class samp {
double *p;
public:
samp (do d) {
p = (double *) malloc(sizeof(double));
if (!p) exit (1); //allocation error
*p = d;
}
~samp() {free(p) ;}
//...
}; ...(Solved)
Given this class fragment,
class samp {
double *p;
public:
samp (do d) {
p = (double *) malloc(sizeof(double));
if (!p) exit (1); //allocation error
*p = d;
}
~samp() {free(p) ;}
//...
};
//...
samp ob1(1, ob2(0.0);
//...
ob2 = ob1;
what problem is caused by the assignment of ob1 to ob2?
Date posted: May 12, 2018. Answers (1)
- To illustrate exactly when an object is constructed and destructed when returned from a function, create a C++ class called who. Have who's constructor take...(Solved)
To illustrate exactly when an object is constructed and destructed when returned from a function, create a C++ class called who. Have who's constructor take one character argument that will be used to identify an object.Have the constructor display a message similar to this when constructing an object:
Constructing who #X
where x is the identifying character associated with each object when an object is destroyed, have a message similar to this displayed:
Destroying who #x
where, again, x is the identifying character. Finally, create a function called make_who() that returns a who object. Give each object a unique name.Note the output displayed by the program.
Date posted: May 12, 2018. Answers (1)
- other than the incorrect freeing of dynamically allocated memory, think of a situation in which it would be improper to return an object from a...(Solved)
other than the incorrect freeing of dynamically allocated memory, think of a situation in which it would be improper to return an object from a function.
Date posted: May 12, 2018. Answers (1)
- As you know, when an object is passed to a function, a copy of that object is made.Further, when that function returns, the copy's destructor...(Solved)
As you know, when an object is passed to a function, a copy of that object is made.Further, when that function returns, the copy's destructor function is called.Keeping this in mind, what is wrong with the following program?
// This program contains an error.
#include
#include
using namespace std;
class dyna {
int *p;
public:
dyna(int i);
~dyna() { free(p); cout << "freeing \n"; }
int get() { return *p; }
};
dyna::dy*) malloc(sizeof(int));
if(!p) {
cout << "Allocation failure\";
exit(1);
}
*p = i;
}
// Return negative value of *ob.p
int neg(dyna ob)
{
retur.get();
}
int main()
{
dyna 0(-10);
cout << o.get() << "\n";
cout << neg(o) << "\n";
dyna o2(20);
cout << o2.get () << "\n";
cout << neg (o2)\n";
cout << o.get () << "\n";
cout << neg (o) << "\n";
return 0;
}
Date posted: May 12, 2018. Answers (1)
- If a queue dynamically allocates memory to hold the queue, explain the reason for that occurence and state whether in such a situation it...(Solved)
If a queue dynamically allocates memory to hold the queue, explain the reason for that occurence and state whether in such a situation it is possible to block one queue from being assigned to another.
Date posted: May 12, 2018. Answers (1)
- What is wrong with the following fragment?
//This program has an error.
#include
using namespace std;
class c11 {
int i, j;
public:
c11 (it a, int b) { i =...(Solved)
What is wrong with the following fragment?
//This program has an error.
#include
using namespace std;
class c11 {
int i, j;
public:
c11 (it a, int b) { i = a; j = b; }
// ...
};
class c12 {
int i; j;
public:
c12 (int a, int b) { i = a; j = b; }
// ...
};
int main()
{
c11 x(1c12 y(0, 0);
x = y;
// ...
}
Date posted: May 12, 2018. Answers (1)
- Given the following class, show how an object called ob that passes the value 100 to a and X to c would be declared
class sample...(Solved)
Given the following class, show how an object called ob that passes the value 100 to a and X to c would be declared
class sample {
int a;
char c;
public:
sample(int x, char ch) {a = x; c = ch;}
//...
};
Date posted: May 12, 2018. Answers (1)
- Given the following base class, show how it can be inherited by a derived class called mars
class planet {
int moons;
double dist_from_sun;
double diameter;
double mass
public:
// ...
};(Solved)
Given the following base class, show how it can be inherited by a derived class called mars
class planet {
int moons;
double dist_from_sun;
double diameter;
double mass
public:
// ...
};
Date posted: May 12, 2018. Answers (1)
- Given the following class, what are the names of its constructor and destructor functions?
class widgit {
int x, y;
public :
//.....fill in constructor and destructor functions
};(Solved)
Given the following class, what are the names of its constructor and destructor functions?
class widgit {
int x, y;
public :
//.....fill in constructor and destructor functions
};
Date posted: May 12, 2018. Answers (1)
- Create a class called dice that contains one private integer variable.Create a function called roll() that uses the standard randomn number generator, rand(), to generate...(Solved)
Create a class called dice that contains one private integer variable.Create a function called roll() that uses the standard randomn number generator, rand(), to generate a number between 1 and 6. Then have roll() display that value.
Date posted: May 12, 2018. Answers (1)
- Create a class called prompt in C++ language.Pass its constructor function a prompting string of your choice.Have the constructor display the string and then input...(Solved)
Create a class called prompt in C++ language.Pass its constructor function a prompting string of your choice.Have the constructor display the string and then input an integer.Store this value in a private variable called count.When an object of type prompt is destroyed, ring the bell on the terminal as many times as the user entered.
Date posted: May 12, 2018. Answers (1)
- Is the following fragment valid?
union {
float f;
unsigned int bits;
};(Solved)
Is the following fragment valid?
union {
float f;
unsigned int bits;
};
Date posted: May 12, 2018. Answers (1)
- Modify the following program so that all member functions are automatically in-lined:
#include
using namespace std;
class myclass {
int i, j;
public:
myclass (int x, int y);
void show();
};
myclass ::...(Solved)
Modify the following program so that all member functions are automatically in-lined:
#include
using namespace std;
class myclass {
int i, j;
public:
myclass (int x, int y);
void show();
};
myclass :: myclass(int x, int y)
{
i=x;
j=y;
}
void myclass :: show()
{
cout << i << " " <}
int main()
{
myclass count (2, 3);
count.show();
return 0;
}
Date posted: May 12, 2018. Answers (1)
- What does the following program display?
#include
using namespace std;
int main()
{
int i = 10;
long 1 = 1000000;
double d = -0.0009;
cout << i << ' ' <<1<<...(Solved)
What does the following program display?
#include
using namespace std;
int main()
{
int i = 10;
long 1 = 1000000;
double d = -0.0009;
cout << i << ' ' <<1<< ' '<cout << "\n";
return 0;
}
Date posted: May 12, 2018. Answers (1)
- Create a C++ class called line that draws a line on the screen.Store the line length in a private integer variable called len.Have line's constructor...(Solved)
Create a C++ class called line that draws a line on the screen.Store the line length in a private integer variable called len.Have line's constructor take one parameter: the line length.Have the constructor store the length and actually draw the line .If the system does not support graphics, display the line by using *. Give the line a destructor that erases the line.
Date posted: May 12, 2018. Answers (1)
- Why might the following function not be in-lined by the computer' s compiler
void f1()
{
int i;
for(i=0; i<10; i++) cout <(Solved)
Why might the following function not be in-lined by the computer' s compiler
void f1()
{
int i;
for(i=0; i<10; i++) cout <}
Date posted: May 12, 2018. Answers (1)
- Explain what an anonymous union is and how it differs from a normal union.(Solved)
Explain what an anonymous union is and how it differs from a normal union.
Date posted: May 12, 2018. Answers (1)
- Use a C++ union class to swap the low- and high-order bytes of an integer (assuming 16-bit integer; if the computer uses 32-bit integers, swap...(Solved)
Use a C++ union class to swap the low- and high-order bytes of an integer (assuming 16-bit integer; if the computer uses 32-bit integers, swap the bytes of a short int)
Date posted: May 12, 2018. Answers (1)
- Given the following base C++ class,
class area_cl {
public:
double height;
double width;
};
Create two derived classes called rectangle and isosceles that inherit area_cl. Have each class include a...(Solved)
Given the following base C++ class,
class area_cl {
public:
double height;
double width;
};
Create two derived classes called rectangle and isosceles that inherit area_cl. Have each class include a function called area()
that returns the area of a rectangle or isosceles triangle, as appropriate. Use parameterized constructors to initialize height and width.
Date posted: May 12, 2018. Answers (1)