linkedlist_add.cpp

// C++ program for addition of two polynomials
// using Linked Lists
#include<bits/stdc++.h>
using namespace std;
// Node structure containing power and coefficient of variable
struct Node
{
int coeff;
int pow;
struct Node *next;
};
// Function to create new node
void create_node(int x, int y, struct Node **temp)
{
struct Node *r, *z;
z = *temp;
if(z == NULL)
{
r =(struct Node*)malloc(sizeof(struct Node));
r->coeff = x;
r->pow = y;
*temp = r;
r->next = (struct Node*)malloc(sizeof(struct Node));
r = r->next;
r->next = NULL;
}
else
{
r->coeff = x;
r->pow = y;
r->next = (struct Node*)malloc(sizeof(struct Node));
r = r->next;
r->next = NULL;
}
}
// Function Adding two polynomial numbers
void polyadd(struct Node *poly1, struct Node *poly2, struct Node
*poly)
{
while(poly1->next && poly2->next)
{
// If power of 1st polynomial is greater then 2nd, then store 1st as it
is
// and move its pointer
if(poly1->pow > poly2->pow)
{
poly->pow = poly1->pow;
poly->coeff = poly1->coeff;
poly1 = poly1->next;
}
// If power of 2nd polynomial is greater then 1st, then store 2nd as it
is
// and move its pointer
else if(poly1->pow < poly2->pow)
{
poly->pow = poly2->pow;
poly->coeff = poly2->coeff;
poly2 = poly2->next;
}
// If power of both polynomial numbers is same then add their
coefficients
else
{
poly->pow = poly1->pow;
poly->coeff = poly1->coeff+poly2->coeff;
poly1 = poly1->next;
poly2 = poly2->next;
}
// Dynamically create new node
poly->next = (struct Node *)malloc(sizeof(struct Node));
poly = poly->next;
poly->next = NULL;
}
while(poly1->next || poly2->next)
{
if(poly1->next)
{
poly->pow = poly1->pow;
poly->coeff = poly1->coeff;
poly1 = poly1->next;
}
if(poly2->next)
{
poly->pow = poly2->pow;
poly->coeff = poly2->coeff;
poly2 = poly2->next;
}
poly->next = (struct Node *)malloc(sizeof(struct Node));
poly = poly->next;
poly->next = NULL;
}
}
// Display Linked list
void show(struct Node *node)
{
while(node->next != NULL)
{
printf("%dx^%d", node->coeff, node->pow);
node = node->next;
if(node->next != NULL)
printf(" + ");
}
}
// Driver program
int main()
{
struct Node *poly1 = NULL, *poly2 = NULL, *poly = NULL;
// Create first list of 5x^2 + 4x^1 + 2x^0
create_node(5,2,&poly1);
create_node(4,1,&poly1);
create_node(2,0,&poly1);
// Create second list of 5x^1 + 5x^0
create_node(5,1,&poly2);
create_node(5,0,&poly2);
printf("1st Number: ");
show(poly1);
printf("\n2nd Number: ");
show(poly2);
poly = (struct Node *)malloc(sizeof(struct Node));
// Function add two polynomial numbers
polyadd(poly1, poly2, poly);
// Display resultant List
printf("\nAdded polynomial: ");
show(poly);
return 0;
}

// Output:
// 1st Number: 5x^2 + 4x^1 + 2x^0
// 2nd Number: 5x^1 + 5x^0
// Added polynomial: 5x^2 + 9x^1 + 7x^0
// Time Complexity: O(m + n) where m and n are number of nodes in first
// and second lists respectively.