C function for addition of two single variable polynomials

Replies

• 

  upgrade

  c code
  
  can anyone giv me c code for addition of two single variable polynomials.
• 

  mahul

  please be a little more elaborate if u can, like how u represent and store ur polynomials, the arguments u would like to pass to ur function and such stuff. By what u have posted, there was very little that i could comprehend.
• 

  upgrade

  i want to accept any length two polynomials like say 6x^3+5x^2
  and 4x^2+5x+7
  now i hav to take powers and coefficients of x from user.i hav done that.
  but now i need to add these polynomials.
• 

  friendster7

  mynode *polynomial_add(mynode *h1, mynode *h2, mynode *h3)
  {
  mynode *p1, *p2;
  int x1, x2, y1, y2, cf1, cf2, cf;
  
  p1 = h1->next;
  
  while(p1!=h1)
  {
  x1 = p1->px;
  y1 = p1->py;
  cf1 = p1->cf;
  
  // Search for this term in the second polynomial
  
  p2 = h2->next;
  
  while(p2 != h2)
  {
  x2 = p2->px;
  y2 = p2->py;
  cf2 = p2->cf;
  
  if(x1 == x2 && y1 == y2)break;
  
  p2 = p2->next;
  
  }
  
  
  if(p2 != h2)
  {
  // We found something in the second polynomial.
  
  cf = cf1 + cf2;
  p2->flag = 1;
  
  if(cf!=0){h3=addNode(cf,x1,y1,h3);}
  }
  else
  {
  h3=addNode(cf,x1,y1,h3);
  }
  
  p1 = p1->next;
  
  }//while
  
  
  // Add the remaining elements of the second polynomail to the result
  
  while(p2 != h2)
  {
  if(p2 -> flag ==0)
  {
  h3=addNode(p2->cf, p2->px, p2->py, h3);
  }
  p2=p2->next;
  }
  
  return(h3);
  }

  this will help u i guess..this can add two polynomials
• 

  Ashutosh_shukla

  I just joined the site and would like to contribute in here
  Code in PASCAL using linked list
  {Program to perform polynomial addition using linked list}
  

  PROGRAM polyaddll(input,output);
  TYPE nodeptr=^node;
       node=RECORD
       coef:integer;
       exp:integer;
       link:nodeptr;
       END;
  VAR one,two,res:nodeptr;
      k:integer;
  PROCEDURE print(n:nodeptr);
  VAR p:nodeptr;
  BEGIN
       p:=n;
       WHILE (p<>NIL) DO
       BEGIN
            write(p^.coef,' X^ ',p^.exp);
            IF (p^.link<>NIL) THEN
               write(' + ');
            p:=p^.link;
       END;
       writeln;
  END;
  PROCEDURE create(VAR n:nodeptr);
  VAR p,q:nodeptr;
      c:char;
  BEGIN
       c:='y';
       WHILE (c<>'n') DO
       BEGIN
            new(p);
            write('Enter the coefficient of the term : ');
            readln(k);
            p^.coef:=k;
            write('Enter the exponent of the term : ');
            readln(k);
            p^.exp:=k;
            p^.link:=NIL;
            write('Do you want to add any more terms (Y/N) : ');
            readln(c);
            IF (n=NIL) THEN
            BEGIN
                 n:=p;
                 q:=p;
            END
            ELSE
            BEGIN
                 q^.link:=p;
                 q:=p;
            END;
       END;
  END;
  PROCEDURE sum(VAR a,b,c:nodeptr);
  VAR p,q,r,s:nodeptr;
  BEGIN
       p:=a;
       q:=b;
       WHILE ((p<>NIL) AND (q<>NIL)) DO
       BEGIN
            new(r);
            r^.link:=NIL;
            IF (p^.exp>q^.exp) THEN
            BEGIN
                 r^.coef:=p^.coef;
                 r^.exp:=p^.exp;
                 p:=p^.link;
            END
            ELSE
                IF (q^.exp>p^.exp) THEN
                BEGIN
                     r^.coef:=q^.coef;
                     r^.exp:=q^.exp;
                     q:=q^.link;
                END
                ELSE
                BEGIN
                     r^.coef:=p^.coef+q^.coef;
                     r^.exp:=p^.exp;
                     p:=p^.link;
                     q:=q^.link;
                END;
            IF (c=NIL) THEN
            BEGIN
                 c:=r;
                 s:=r;
            END
            ELSE
            BEGIN
                 s^.link:=r;
                 s:=r;
            END;
       END;
       WHILE (p<>NIL) DO
       BEGIN
            new(r);
            r^.coef:=p^.coef;
            r^.exp:=p^.exp;
            r^.link:=NIL;
            p:=p^.link;
            IF (c=NIL) THEN
            BEGIN
                 c:=r;
                 s:=r;
            END
            ELSE
            BEGIN
                 s^.link:=r;
                 s:=r;
            END;
       END;
       WHILE (q<>NIL) DO
       BEGIN
            new(r);
            r^.coef:=q^.coef;
            r^.exp:=q^.exp;
            r^.link:=NIL;
            q:=q^.link;
            IF (c=NIL) THEN
            BEGIN
                 c:=r;
                 s:=r;
            END
            ELSE
            BEGIN
                 s^.link:=r;
                 s:=r;
            END;
       END;
  END;
  BEGIN
       one:=NIL;
       two:=NIL;
       res:=NIL;
       writeln('Enter the first polynomial : ');
       create(one);
       writeln('Enter the second polynomial : ');
       create(two);
       writeln('The first polynomial is  : ');
       print(one);
       writeln('The second polynomial is : ');
       print(two);
       sum(one,two,res);
       writeln('The reult of addition is : ');
       print(res);
       readln;
  END.

  We Rock!!!!!!!
• 

  pradeep_agrawal

  Hi friendster7,
  
  I did not tried running your code but here are some of my view:
  1. Since you are initilizing p1 & p2 with next of h1 & h2 and then comparing for (p1 != h1) and (p2 != h2), the conditions will not meet.
  2. Code for addNode is required.
  
  Here is my sample code for the given problem statement.
  
  

  #include "stdio.h"
  
  typedef struct node {
    int cof;
    int pow;
    struct node *next;
  } nodet;
  
  nodet* createnewnode(int cof, int pow) {
    nodet* newnode = (nodet*)malloc(sizeof(nodet));
    newnode->cof = cof;
    newnode->pow = pow;
    newnode->next = NULL;
    return newnode;
  }
  
  void deletepoly(nodet* head) {
    nodet* temp = NULL;
    while(head != NULL) {
      temp = head;
      head = head->next;
      free(temp);
    }
  }
  
  void displaypoly(nodet* head) {
    if(head == NULL) {
      printf("Empty polynomial\n");
    } else {
      do {
        if(head->cof > 0) {
          printf("+");
        }
        if((head->cof == 1) && (head->pow == 0)) {
          printf("1");
        } else {
          if(head->cof != 1) {
            printf("%d", head->cof);
          }
          if(head->pow != 0) {
            printf("x");
            if(head->pow != 1) {
              printf("^%d", head->pow);
            }
           printf(" ");
          }
        }
        head = head->next;
      } while(head != NULL);
      printf("\n");
    }
  }
  
  nodet* addpoly(nodet* poly1, nodet* poly2) {
    nodet* newnode = NULL;
    nodet* retnode = NULL;
    nodet* retnodelast = NULL;
    nodet* temp = NULL;
    nodet* temp1 = poly1;
    nodet* temp2 = poly2;
    int cof = 0;
    int pow = 0;
  
    while((temp1 != NULL) && (temp2 != NULL)) {
      if(temp1->pow > temp2->pow) {
        cof = temp1->cof;
        pow = temp1->pow;
        temp1 = temp1->next;
      } else if(temp1->pow == temp2->pow) {
        cof = temp1->cof + temp2->cof;
        pow = temp1->pow;
        temp1 = temp1->next;
        temp2 = temp2->next;
      } else {
        cof = temp2->cof;
        pow = temp2->pow;
        temp2 = temp2->next;
      }
      if(cof != 0) {
        newnode = createnewnode(cof, pow);
        if(retnode == NULL) {
          retnode = newnode;
          retnodelast = retnode;
        } else {
          retnodelast->next = newnode;
          retnodelast = retnodelast->next;
        }
      }
    }
  
    if(temp1 != NULL) {
      temp = temp1;
    } else {
      temp = temp2;
    }
  
    while(temp != NULL) {
      newnode = createnewnode(temp->cof, temp->pow);
      if(retnode == NULL) {
        retnode = newnode;
        retnodelast = retnode;
      } else {
        retnodelast->next = newnode;
        retnode = retnode->next;
      }
      temp = temp->next;    
    }
  
    return retnode;
  }
  
  int main() {
    nodet *poly1 = NULL;
    nodet *poly2 = NULL;
    nodet *polysum = NULL;
    nodet* newnode = NULL;
    nodet* temp = NULL;
    int order_poly1 = 0;
    int order_poly2 = 0;
    int cof = 0;
    int i = 0;
  
    //read polynomial 1
    scanf("%d", &order_poly1);
    if(order_poly1 < 0) {
      printf("Polynomial of invalid order\n");
      return 0;
    }
  
    for(i = order_poly1; i >= 0; i--) {
      scanf("%d", &cof);
      if(cof != 0) {
        newnode = createnewnode(cof, i);
        if(poly1 == NULL) {
          poly1 = newnode;
          temp = poly1;
        } else {
          temp->next = newnode;
          temp = temp->next;
        }
      }
    }
  
    //read polynomial 2
    scanf("%d", &order_poly2);
    if(order_poly2 < 0) {
      printf("Polynomial of invalid order\n");
      deletepoly(poly1);
      return 0;
    }
  
    for(i = order_poly2; i >= 0; i--) {
      scanf("%d", &cof);
      if(cof != 0) {
        newnode = createnewnode(cof, i);
        if(poly2 == NULL) {
          poly2 = newnode;
          temp = poly2;
        } else {
          temp->next = newnode;
          temp = temp->next;
        }
      }
    }
  
    //display polynomial 1
    printf("Polynomial 1:\n");
    displaypoly(poly1);
  
    //display polynomial 2
    printf("Polynomial 2:\n");
    displaypoly(poly2);
  
    //add polynomials & display resultant polynomial
    polysum = addpoly(poly1, poly2);
    printf("Result Polynomial:\n");
    displaypoly(polysum);
  
    //delete polynomials
    deletepoly(poly1);
    deletepoly(poly2);
    deletepoly(polysum);
  
    return 0;
  }
  

  Compile the file with above code and run as:
  a.exe < input.txt > output.txt [on windows]
  a.out < input.txt > output.txt [on linux]
  
  Here,
  a.exe or a.out are the executables generated after compilation
  
  input.txt is the file containing input, e.g., if the polynomials are
  P1: 4x^2 + x + 1
  P2: 5x^3 -4x^2 - 1
  Then input.txt will be
  

  2
  4
  1
  1
  3
  5
  -4
  0
  -1

  2
  4
  1
  1
  
  2 represent order of polynomial (4x^2 + x + 1) and then each number represents coefficients

  3
  5
  -4
  0
  -1
  
  3 represent order of polynomial (5x^3 -4x^2 - 1) and then each number represents coefficients

  output.txt is the output file containing result, for given example output.txt will contain
  

  Polynomial 1:
  +4x^2 +x +1
  Polynomial 2:
  +5x^3 -4x^2 -1
  Result Polynomial:
  +5x^3 +x

  -Pradeep