Pointer To Functions In C++

#include
using namespace std;

int addition (int a, int b)
{ return (a+b); }

int subtraction (int a, int b)
{ return (a-b); }

int operation (int x, int y, int (*functocall)(int,int))
{
  int g;
  g = (*functocall)(x,y);
  return (g);
}

int main ()
{
  int m,n;
  int (*minus)(int,int) = subtraction;

  m = operation (7, 5, addition);
  n = operation (20, m, minus);
  cout <  return 0;
}

Example Of Pointer In C++

#include
using namespace std;
int main ()
{
int firstvalue, secondvalue;
int * mypointer;
mypointer = &firstvalue;
*mypointer = 10;
mypointer = &secondvalue;
*mypointer = 20;
cout << "firstvalue is " << firstvalue << endl;
cout << "secondvalue is " << secondvalue << endl;
return 0;
}

Factorial off a number using "do while" loop

#include
#include
void main(){int n,f=1;clrscr();printf("enter any number=");scanf("%d",&n);do{f=f*n;n--;}while(n>0);printf("factorial number is=%d",f);getch();}

Example Of XOR In C

#include
#include

struct xnode
{
int data;
unsigned long direction;
};
struct xnode *add_data(int data, struct xnode* list);
void walk_list(struct xnode *list);
int main(void)
{
struct xnode *l2 = add_data(2, NULL);
struct xnode *l1 = add_data(1, l2);
struct xnode *l3 = add_data(3, l2);
struct xnode *l4 = add_data(4, l3);
printf("front -> back....\n");
walk_list(l1);
printf("back -> front....\n");
walk_list(l4);
return 0;
}
struct xnode *add_data(int data, struct xnode *list)
{
struct xnode *newxnode = malloc(sizeof(struct xnode));
assert(newxnode);
newxnode->direction = (unsigned long)list;
newxnode->data = data;
if(list != NULL)
list->direction ^= (unsigned long)newxnode;
return newxnode;
}
void walk_list(struct xnode *list)
{
unsigned long prev = 0;
while(list != NULL) {
unsigned long next = prev ^ list->direction;
printf("%d ", list->data);
prev = (unsigned long)list;
list = (struct xnode *)next;
}
printf("\n");
}

Using C Program Print Fibonacci sequence 1 1 2 3 5 8 13 21 34 55 89 ...

1 1 2 3 5 8 13 21 34 55 89 ...

#include
void main()
{

static int prev_number=0, number=1; // static: so value is not lost

int fibonacci (int prev_number, int number);

printf ("Following are the first 25 Numbers of the Fibonacci Series:\n");

printf ("1 "); //to avoid complexity

fibonacci (prev_number,number);

}


fibonacci (int prev_number, int number)

{
static int i=1; //i is not 0, cuz 1 is already counted in main.
int fibo;

if (i==25)
{
printf ("\ndone"); //stop after 25 numbers

}

else
{
fibo=prev_number+number;
prev_number=number; //important steps

number=fibo;

printf ("\n%d", fibo);
i++; // increment counter

fibonacci (prev_number,number); //recursion

}

}

Program to calculate the factorial of a number. Use the concept of recursion instead of using loops.

#include

void main()

{

int a, fact;


printf("\nEnter any number: ");

scanf ("%d", &a);

fact=rec (a);

printf("\nFactorial Value = %d", fact);

}

rec (int x)

{

int f;


if (x==1)

return (1);

else

f=x*rec(x-1);


return (f);

}

C Program For DFA End With 11

#include
#include
void CreateDFA();
int StateMoveInDFA(int,char);
char Letters[10];
int NoOfInputLetter,NoOfStates,NoOfFinalState;
int FinalStates[5];
int DFA[10][10];
void main()
{
int s,i,Accepted;
char Line[10];
CreateDFA();
do
{
s=0;
i=0;
Accepted= 0;
printf("\n\nEnter Input String.. ");
scanf("%s",Line);
while(Line[i]!='\0')
if((s=StateMoveInDFA(s,Line[i++]))<0 p="">break;
for(i=0 ;iif(FinalStates[i] ==s )
Accepted= 1;
(Accepted)?printf("\nInputted String is Valid...") : printf("\nInputed String is Not Valid...");
getch();
printf("\n\nDo you want to continue..??(y/n)");
}
while(getch()=='y' || getch()=='Y');
}
void CreateDFA()
{
int i,j;
char c;
printf("Enter the no. of states.. ");
scanf("%d",&NoOfStates);
printf("Enter the no. of input letters.. ");
scanf("%d",&NoOfInputLetter);
printf("Enter the no. of final states.. ");
scanf("%d",&NoOfFinalState);
for(i=0;iprintf("Final state %d : ",i+1);
scanf("%d",&FinalStates[i]);
}
for(i=0;iprintf("\nInput Letter %d :",i+1);
printf("%c",Letters[i]=getch());
}
printf("\nEnter the State Movements In DFA...\n");
for(i=0;ifor(j=0;jprintf("Move(%d,%c) : ",i,Letters[j]);
scanf("%d",&DFA[i][j]);
}
}
}
int StateMoveInDFA(int s,char c)
{
int j;
for(j=0;jif(c==Letters[j])
return(DFA[s][j]);
return -1;
}