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The terms confusion and diffusion were introduced by Claude Shannon to capture the two basic building blocks for any cryptographic system [8]. Shannon’s concern was to thwart cryptanalysis based on statistical analysis.
Diffusion and confusion are the two cornerstones of block cipher design, these are:
•?Diffusion means that each plaintext bit must affect as many ciphertext bits as possible.
•?Confusion in this context means that the relationship between the encryption key and the
ciphertext must be as complex as possible. Another way of describing confusion would be that each bit of the key must affect as many bits as possible of the output ciphertext block
lydiajane74 answered the question on May 13, 2018 at 23:30
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Date posted: May 13, 2018. Answers (1)
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- 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
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Date posted: May 12, 2018. Answers (1)
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Date posted: May 12, 2018. Answers (1)
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// 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)
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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)
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Date posted: May 12, 2018. Answers (1)
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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)
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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)
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Date posted: May 12, 2018. Answers (1)