crc-ccitt is based on the polynomial x^16+x^12+x^5+1

How to write a C Program crc-ccitt which based on the polynomial x^16+x^12+x^5+1 in C Programming Language ?

The prescription for determining the mask to use for a given polynomial is as follows:

                1.  Represent the polynomial by a 17-bit number
                2.  Assume that the most and least significant bits are 1
                3.  Place the right 16 bits into an integer

Solution:

1. /* compute crc's */
2. /* crc-ccitt is based on the polynomial x^16+x^12+x^5+1 */
3. /* The prescription for determining the mask to use for a given polynomial
4.         is as follows:
5.                 1.  Represent the polynomial by a 17-bit number
6.                 2.  Assume that the most and least significant bits are 1
7.                 3.  Place the right 16 bits into an integer
8. */
10. #include        <stdio.h>
11. #include        <stdlib.h>
12. #include        <string.h>
13. #include        <time.h>
15. #define         MTT     0x1021          /* crc-ccitt mask */
16. #define     CLK_TCK CLOCKS_PER_SEC
18. /* function declarations */
19. unsigned short int updcrc(unsigned short int,int,unsigned short int);
20. void perr(char *);
22. /* variables */
23. char filename[100];
24. unsigned short int crctt;
25. int ch;
26. unsigned long num;
27. FILE *fp;
29. /* driver */
30. int main(argc,argv)
31. int argc; char **argv;
32. {
33.  clock_t start,end;
34.         if(argc>2) perr("Usage:  ccitt [filename]");
35.         if(argc==2) strcpy(filename,argv[1]);
36.         else
37.         {
38.                 printf("\nEnter filename:  ");
39.                 gets(filename);
40.         }
41.         if((fp=fopen(filename,"rb"))==NULL) perr("Can't open file");
42.         num=0L; crctt=0;
43.         start=clock();
44.        
45.         while((ch=fgetc(fp))!=EOF)
46.         {
47.                 //if (ch == '\n')
48.                 //      continue;
49.                 num++;
50.                 //int i; for (i=0;i<10000;i++){
51.                 crctt=updcrc(crctt,ch,MTT);
52.                 //}
53.         }
54.         end=clock();
55.         fclose(fp);
56.         printf("\nNumber of bytes = %lu\n CRCTT = %04X\n",      num,crctt);
57.         printf("Czas trwania: %f\n",(double)(end-start)/CLK_TCK);
58.         return 0;
59. }
61. /* update crc */
62. unsigned short int updcrc(crc,c,mask)
63. unsigned short int crc,mask; int c;
64. {
65.         int i;
66.         c<<=8;
67.         for(i=0;i<8;i++)
68.         {
69.                 if((crc ^ c) & 0x8000) crc=(crc<<1)^mask;
70.                 else crc<<=1;
71.                 c<<=1;
72.         }
73.         return crc;
74. }
76. /* error abort */
77. void perr(s)
78. char *s;
79. {
80.         printf("\n%s",s); exit(1);
81. }

C Program To Multiply Two Polynomials

How to in Write a  C program to multiply two polynomials in C Programming Language ?

Solution:
/*
Write a C program to multiply two polynomials.
*/

Adding two polynomial functions C Program Using Structure

How to write a C Program to Adding Two Polynomial Functions in C Programming Language ?

Solution:
/*Adding two polynomial functions*/

#include <stdio.h>
#include<stdlib.h>

struct poly* link(struct poly*);
void display(struct poly*);
struct poly* addlink(struct poly*,struct poly*, struct poly*);

struct poly
{
int coeff, pow;
struct poly *ptr;
};

int main()
{
struct poly *head1,*head2,*head3;
int num;
head1=NULL;
head2=NULL;
head3=NULL;

while(1)
{
printf("\nEnter\n1->To create first polynomial function\n2->To create second polynomial function\n3->To display first polynomial function\n4->To display second polynomial function\n5->To add both the polynomial functions\n6->To display the new polynomial created after addition\n");
scanf("%d",&num);

switch(num)
{

case 1: head1=link(head1);
break;

case 2: head2=link(head2);
break;

case 3: display(head1);
break;

case 4: display(head2);
break;

case 5: head3=addlink(head1,head2,head3);
break;

case 6: display(head3);
break;

default: printf("\nBoss ! Enter the correct value\n");

}
}
}

struct poly* link(struct poly *head1)
{
struct poly *newnode,*temp;
int value,degree;
newnode=temp=NULL;
printf("\nEnter the coefficient of the polynomial\n");
scanf("%d",&value);
printf("\nEnter the degree for variable x\n");
scanf("%d",&degree);

newnode=(struct poly*) malloc (sizeof (struct poly));

newnode->pow=degree;
newnode->coeff=value;
temp=head1;

if(temp==NULL)
{
printf("\nThe first node is created\n");
newnode->ptr=NULL;
return newnode;
}
else
{
printf("\nThe next node is being linked\n");
temp->ptr=newnode;
temp=temp->ptr;
return head1;
}

}

void display(struct poly* head)
{
if(head == NULL)
{
printf("\nThe polynomial function is not created.\nPlease create a new polynomial function.\n");
}

while(head != NULL && head->ptr != NULL)
{
printf("The polynomial function has been detected\n");
printf("%dx^%d+",head->coeff,head->pow);
head=head->ptr;
}

if(head->ptr == NULL)
{
// printf("\nEntering the last node\n");
printf("%dx^%d",head->coeff,head->pow);
head=head->ptr;
}
}


struct poly* addlink(struct poly* head,struct poly* tail,struct poly *head3 )
{
struct poly *temp1,*temp,*newnode;
temp=newnode=temp1=head3=NULL;

newnode=( struct poly*) malloc(sizeof(struct poly));

if( head == NULL || tail == NULL)
{
printf("\nYou have no node to get added\n");
}
if(head !=NULL && tail == NULL)
{
printf("\nThe existing first polynomial is the final polynomial\n");
return head;
}
if(head == NULL && tail !=NULL)
{
printf("\nThe existing second polynomial is the final polynomial\n");
return tail;
}

head3=newnode;

if(head3==NULL)
{
printf("\nEnter a node first\n");
}

if(head3 != NULL)
{
while(head !=NULL && tail !=NULL)
{
if(head->pow > tail->pow)
{
temp=tail;
temp1=head;
while((head->pow) > (temp->pow))
{
printf("\nThe element's degree in first poly. is greater than the second\n");

if(temp->ptr == NULL)
{
newnode->coeff=temp->coeff;
newnode->pow=temp->pow;
newnode->ptr=NULL;
head3=newnode;
return head3;
temp1=temp1->ptr;

}

temp=temp->ptr;
}
printf("\nYou have come to the end of the tail pointer\n");
}

if(tail->pow > head->pow)
{
temp=head;
temp1=tail;
while((tail->pow) > (temp->pow))
{
printf("\nThe element's degree in second poly. is greater than the first\n");

if(temp->ptr ==NULL)
{
newnode->coeff=temp->coeff;
newnode->pow=temp->pow;
newnode->ptr=NULL;
head3=newnode;
return head3;
temp1=temp1->ptr;
}

temp=temp->ptr;
}

printf("\nYou have come to the end of the tail pointer\n");
}

if(head->pow == tail->pow)
{
temp=head;
temp1=tail;

while((temp->pow == temp1->pow))
{
newnode->coeff = (temp->coeff + tail->coeff);
newnode->pow=temp->pow;
head3=newnode;
return head3;
temp=temp->ptr;
temp1=temp1->ptr;
}
}
}
}

}

Program to Add Two Polynomials Using Linked List C Program

How to write a C Program to add two polynomials using linked list in C Programming Language ?

Solution:
/*Program to add two polynomials using linked list*/

#include <stdio.h>
#include<stdlib.h>

struct poly* link(struct poly*);
void display(struct poly*);
struct poly* addlink(struct poly*,struct poly*, struct poly*);

struct poly
{
int coeff, pow;
struct poly *ptr;
};

int main()
{
struct poly *head1,*head2,*head3;
int num;
head1=NULL;
head2=NULL;
head3=NULL;

while(1)
{
printf("\nEnter\n1->To create first polynomial function\n2->To create second polynomial function\n3->To display first polynomial function\n4->To display second polynomial function\n5->To add both the polynomial functions\n6->To display the new polynomial created after addition\n");
scanf("%d",&num);

switch(num)
{

case 1: head1=link(head1);
break;

case 2: head2=link(head2);
break;

case 3: display(head1);
break;

case 4: display(head2);
break;

case 5: head3=addlink(head1,head2,head3);
break;

case 6: display(head3);
break;

default: printf("\nBoss ! Enter the correct value\n");

}
}
}

struct poly* link(struct poly *head1)
{
struct poly *newnode;
int value,degree;
newnode=NULL;
printf("\nEnter the coefficient of the polynomial\n");
scanf("%d",&value);
printf("\nEnter the degree for variable x\n");
scanf("%d",&degree);

newnode=(struct poly*) malloc (sizeof (struct poly));

newnode->pow=degree;
newnode->coeff=value;

if(head1==NULL)
{
printf("\nThe first node is created\n");
newnode->ptr=NULL;
}
else
{
printf("\nThe next node is being linked\n");
newnode->ptr=head1;
}
return newnode;
}

void display(struct poly* head)
{
if(head == NULL)
{
printf("\nThe polynomial function is not created.\nPlease create a new polynomial function.\n");
}

while(head != NULL && head->ptr != NULL)
{
printf("The polynomial function has been detected\n");
printf("%dx^%d+",head->coeff,head->pow);
head=head->ptr;
}

if(head->ptr == NULL)
{
printf("\nEntering the last node\n");
printf("%dx^%d",head->coeff,head->pow);
head=head->ptr;
}
}


struct poly* addlink(struct poly* head,struct poly* tail,struct poly *head3 )
{
struct poly *temp1,*temp,*newnode;
temp=newnode=temp1=head3=NULL;

newnode=( struct poly*) malloc(sizeof(struct poly));

if( head == NULL || tail == NULL)
{
printf("\nYou have no node to get added\n");
}
if(head !=NULL && tail == NULL)
{
printf("\nThe existing first polynomial is the final polynomial\n");
return head;
}
if(head == NULL && tail !=NULL)
{
printf("\nThe existing second polynomial is the final polynomial\n");
return tail;
}

head3=newnode;

if(head3==NULL)
{
printf("\nEnter a node first\n");
}

if(head3 != NULL)
{
while(head !=NULL && tail !=NULL)
{
if(head->pow > tail->pow)
{
temp=tail;
temp1=head;
while((head->pow) > (temp->pow))
{
printf("\nThe element's degree in first poly. is greater than the second\n");

if(temp->ptr == NULL)
{
newnode->coeff=temp->coeff;
newnode->pow=temp->pow;
newnode->ptr=NULL;
head3=newnode;
return head3;
temp1=temp1->ptr;

}

temp=temp->ptr;
}
printf("\nYou have come to the end of the tail pointer\n");
}

if(tail->pow > head->pow)
{
temp=head;
temp1=tail;
while((tail->pow) > (temp->pow))
{
printf("\nThe element's degree in second poly. is greater than the first\n");

if(temp->ptr ==NULL)
{
newnode->coeff=temp->coeff;
newnode->pow=temp->pow;
newnode->ptr=NULL;
head3=newnode;
return head3;
temp1=temp1->ptr;
}

temp=temp->ptr;
}

printf("\nYou have come to the end of the tail pointer\n");
}

if(head->pow == tail->pow)
{
temp=head;
temp1=tail;

while((temp->pow == temp1->pow))
{
newnode->coeff = (temp->coeff + tail->coeff);
newnode->pow=temp->pow;
head3=newnode;
return head3;
temp=temp->ptr;
temp1=temp1->ptr;
}
}
}
}

}