polynomial_sum.c

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

struct node {
	int coeff;
	int exp;
	struct node *next;
};

void insertEnd(struct node **head,int coeff, int exp);
void printList(struct node *head);
struct node* add(struct node *p1, struct node *p2);


int main(){
	struct node *p1 = NULL, *p2=NULL;
	int n, m;
	scanf("%d", &n);
	for(int i=0; i<n; i++){
		int coeff, exp;
		scanf("%d %d", &coeff, &exp);
		insertEnd(&p1, coeff, exp);
	}
	scanf("%d", &m);
	for(int i=0; i<m; i++){
		int coeff, exp;
		scanf("%d %d", &coeff, &exp);
		insertEnd(&p2, coeff, exp);
	}
	printList(p1);
	printList(p2);
	struct node *res = add(p1,p2);
	printList(res);
	int coeff_sum =0;
	while(res!=NULL){
		coeff_sum += res->coeff;
		res = res->next;
	}
	printf("sum : %d", coeff_sum);
}



void insertEnd(struct node **head, int coeff, int exp){
	struct node *new = (struct node *)malloc(sizeof(struct node));
	new->coeff  = coeff;
	new->exp = exp;
	new->next=NULL;
	if(*head==NULL){
		*head=new;
		return;
	}
	struct node *tmp = *head;
	while(tmp->next != NULL)
		tmp = tmp->next;
	tmp->next = new;
}

struct node* add(struct node *p1, struct node *p2){
	struct node *sum = NULL;
	while(p1 != NULL && p2 !=NULL){
		if(p1->exp > p2->exp){
			insertEnd(&sum,p1->coeff, p1->exp);
			p1=p1->next;
		}
		else if(p1->exp < p2->exp){ 
			insertEnd(&sum,p2->coeff, p2->exp); 
			p2=p2->next;
		}
		else{
			insertEnd(&sum, p1->coeff+p2->coeff, p1->exp);
			p1=p1->next;
			p2=p2->next;
		}
	}
	while(p1!=NULL){
		insertEnd(&sum, p1->coeff, p1->exp);
		p1=p1->next;
	}
	while(p2!=NULL){
		insertEnd(&sum, p2->coeff, p2->exp);
		p2=p2->next;
	}
	return sum;
}
void printList(struct node *head){
	struct node *tmp = head;
	while(tmp != NULL){
		printf("(%d, %d) -> ", tmp->coeff, tmp->exp);
		tmp = tmp->next;
	}
	printf("NULL\n");
}