  So, this is our first C program in the blog. We first thought of creating a separate blog for C & C++ related posts, but because of the maintenance issue, we finally decided to merge it to the main blog. So, without any further here is the program.

## #1: What the program does:

This program is a practical implementation of the data structure “Linked List“. We use a linked list to dynamically store user input of polynomial expressions and then we add two polynomials using some simple arithmetic. For this, we follow the simple strategy:

• Make a polynomial abstract datatype using struct which basically implements a linked list.
• We write different functions for Creating (ie, adding more nodes to the linked list) a polynomial function, Adding two polynomials and Showing a polynomial expression.
• Finally we write the main function with menu driven ability to add as many pairs of polynomials the user wants.

## #2: Source Code:

```/**
* @author Swashata
* @for Dearest Froggie
*/

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

/**
* The structure for the polynomial
* This is a linked list with two variable
* int coeff The Coefficient
* int pow The power of x
*/
int coeff;
int pow;
} my_poly;

/** The prototypes */
void my_create_poly(my_poly **);
void my_show_poly(my_poly *);
void my_add_poly(my_poly **, my_poly *, my_poly *);

/**
* The simple menu driven main function
*/
int main(void) {
int ch;
do {
my_poly * poly1, * poly2, * poly3;

printf("\nCreate 1st expression\n");
my_create_poly(&poly1);
printf("\nStored the 1st expression");
my_show_poly(poly1);

printf("\nCreate 2nd expression\n");
my_create_poly(&poly2);
printf("\nStored the 2nd expression");
my_show_poly(poly2);

my_show_poly(poly3);

printf("\nAdd two more expressions? (Y = 1/N = 0): ");
scanf("%d", &ch);
} while (ch);
return 0;
}

/**
* The create polynomial function
* @param my_poly ** node The pointer to the head of the polynomial
* We will modify the parameter and will store the base address
* @return void
*/
void my_create_poly(my_poly ** node) {
int flag; //A flag to control the menu
int coeff, pow;
my_poly * tmp_node; //To hold the temporary last address
tmp_node = (my_poly *) malloc(sizeof(my_poly)); //create the first node
do {
//Get the user data
printf("\nEnter Coeff:");
scanf("%d", &coeff);
tmp_node->coeff = coeff;
printf("\nEnter Pow:");
scanf("%d", &pow);
tmp_node->pow = pow;
//Done storing user data

//Now increase the Linked on user condition
tmp_node->next = NULL;

printf("\nContinue adding more terms to the polynomial list?(Y = 1/N = 0): ");
scanf("%d", &flag);
//printf("\nFLAG: %c\n", flag);
//Grow the linked list on condition
if(flag) {
tmp_node->next = (my_poly *) malloc(sizeof(my_poly)); //Grow the list
tmp_node = tmp_node->next;
tmp_node->next = NULL;
}
} while (flag);
}

/**
* The show polynomial function
* Prints the Polynomial in user readable format
* @param my_poly * node The polynomial linked list
* @return void
*/
void my_show_poly(my_poly * node) {
printf("\nThe polynomial expression is:\n");
while(node != NULL) {
printf("%dx^%d", node->coeff, node->pow);
node = node->next;
if(node != NULL)
printf(" + ");
}
}

/**
* Adds two polynomial to a given variable
* @param my_poly ** result Stores the result
* @param my_poly * poly1 The first polynomial expression
* @param my_poly * poly2 The second polynomial expression
* @return void
*/
void my_add_poly(my_poly ** result, my_poly * poly1, my_poly * poly2) {
my_poly * tmp_node; //Temporary storage for the linked list
tmp_node = (my_poly *) malloc(sizeof(my_poly));
tmp_node->next = NULL;

//Loop while both of the linked lists have value
while(poly1 && poly2) {
if (poly1->pow > poly2->pow) {
tmp_node->pow = poly1->pow;
tmp_node->coeff = poly1->coeff;
poly1 = poly1->next;
}
else if (poly1->pow < poly2->pow) {
tmp_node->pow = poly2->pow;
tmp_node->coeff = poly2->coeff;
poly2 = poly2->next;
}
else {
tmp_node->pow = poly1->pow;
tmp_node->coeff = poly1->coeff + poly2->coeff;
poly1 = poly1->next;
poly2 = poly2->next;
}

//Grow the linked list on condition
if(poly1 && poly2) {
tmp_node->next = (my_poly *) malloc(sizeof(my_poly));
tmp_node = tmp_node->next;
tmp_node->next = NULL;
}
}

//Loop while either of the linked lists has value
while(poly1 || poly2) {
//We have to create the list at beginning
//As the last while loop will not create any unnecessary node
tmp_node->next = (my_poly *) malloc(sizeof(my_poly));
tmp_node = tmp_node->next;
tmp_node->next = NULL;

if(poly1) {
tmp_node->pow = poly1->pow;
tmp_node->coeff = poly1->coeff;
poly1 = poly1->next;
}
if(poly2) {
tmp_node->pow = poly2->pow;
tmp_node->coeff = poly2->coeff;
poly2 = poly2->next;
}
}

}

```

## #3: Output:

So, that was all. If you think there is a better way, or have followed any other algorithm, don’t forget to drop them using comments.

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## C Program: Replacing a substring from a string

1. wakeboards

I have a little bit knowledge of program and some thing got form you. SO thank you dude for your knowledge.

2. Aravind

21.Write a program to add two polynomials. (use structure)

• Swashata Post author

This one uses structure already! Do you want some non-pointer method to do so?

• Sony Augustine

sir i need a non-pointer method to implement this. can you please suggest another method

3. rockie

Hi Friend,

Can you give me any clue/advice on how to start below assignment.

“Create a Node structure called ‘Albums’ and connect a Link list called ‘Artist’ to it.”

4. sachin jagtap

are the code is fine.but during the display function suppose there is -9x^3 is one polynomial and another polynomial is 5x^3 the output expected me is what -4x^3 not +-4x^3 so please send that display function on my email id with
logic(explain that logic)

5. hiral

6. 