Polynomial

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

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


struct node *PolynomailInput(int k) {
    struct node *p = (struct node*)malloc(sizeof(struct node));
    struct node *t = p;
    while(k) {
        t->next = (struct node*)malloc(sizeof(struct node));
        t= t->next;
        printf("Enter Coefficient and Exponent: ");
        scanf("%d %d", &t->co, &t-> exp);
        t->next = NULL;
        k--;
    }
    p=p->next;
    return p;
}

void display(struct node *p) {
    if(p == NULL) printf("Empty Linked List");
    else {
        struct node*x=p;
        while(x!=NULL) {
            printf("%dx^%d ", x->co, x->exp);
            x=x->next;
        }
    }

}

struct node *AddPolynomial(struct node *p, struct node*q) {
    struct node *add = (struct node*)malloc(sizeof(struct node));
    struct node *r = add;
    while(p!=NULL && q!=NULL) {
        r->next = (struct node*)malloc(sizeof(struct node));
        r=r->next;
        if(p->exp==q->exp) {
            r->co = p->co+q->co;
            r->exp = p->exp;
            r->next = NULL;
            p=p->next;
            q=q->next;
        }
        else if(q->exp>p->exp) {
            r->exp = q->exp;
            r->co=q->co;
            r->next = NULL;
            q=q->next;
        }
        else if(p->exp>q->exp) {
            r->exp = p->exp;
            r->co=p->co;
            r->next = NULL;
            p=p->next;
        }
    }
    while(p!=NULL) {
        r->next = (struct node*)malloc(sizeof(struct node));
        r=r->next;
        r->co = p->co;
        r->exp = p->exp;
        r->next = NULL;
        p=p->next;
    }
    while(q!=NULL) {
        r->next = (struct node*)malloc(sizeof(struct node));
        r=r->next;
        r->co = q->co;
        r->exp = q->exp;
        r->next = NULL;
        q=q->next;
    }
    add=add->next;
    return add;
}

struct node *SubPolynomial(struct node *p, struct node *q) {
    struct node *qtemp = (struct node*)malloc(sizeof(struct node));
    struct node *r = qtemp;
    while(q!=NULL) {
        r->next = (struct node*)malloc(sizeof(struct node));
        r=r->next;
        r->co = q->co * (-1);
        r->exp = q->exp;
        r->next = NULL;
        q=q->next;
    }
    qtemp=qtemp->next;
    return AddPolynomial(p,qtemp);
}

struct node *MulPolynomial(struct node *p1, struct node *p2) {
    struct node *p3 = NULL;
    struct node *q = p2;
    while(q!=NULL) {
        struct node *temp = (struct node*)malloc(sizeof(struct node));
        struct node *r = temp;
        struct node *p = p1;
        while(p!=NULL) {
            r->next = (struct node*)malloc(sizeof(struct node));
            r= r->next;
            r->co = p->co*q->co;
            r->exp = p->exp + q->exp;
            r->next = NULL;
            p=p->next;
        }
        temp=temp->next;
        p3=AddPolynomial(p3, temp);
        q=q->next;
    }
    return p3;
}

int main() {
    printf("Enter number of terms of first polynomial function: \n");
    int n;
    scanf("%d", &n);
    struct node* p1= PolynomailInput(n);
    printf("\nEnter number of terms of second polynomial function: \n");
    int m;
    scanf("%d", &m);
    struct node* p2= PolynomailInput(m);
    struct node* sum = AddPolynomial(p1,p2);
    struct node* diff = SubPolynomial(p1,p2);
    struct node* mul = MulPolynomial(p1,p2);
    printf("\nSum of polynomial functions: ");
    display(sum);
    printf("\nDifference of polynomial functions: ");
    display(diff);
    printf("\nMultiplication of polynomial functions: ");
    display(mul);
}