C语言用单链表实现一元多项式的乘法

Question

输入两个一元多项式（指数从高到低），自定义项数，系数和指数，用单链表方法顺序输出求乘积后的多项式的各项系数和指数。

Answer 1

稍等，帮你写一个

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

typedef struct node
{
    int coef;
    int exp;
    struct node* next;
} Node;

Node* create_node(int coef, int exp)
{
    Node* new_node = (Node*)malloc(sizeof(Node));
    new_node->coef = coef;
    new_node->exp = exp;
    new_node->next = NULL;
    return new_node;
}

Node* create_poly(int n)
{
    Node* head = NULL;
    Node* tail = NULL;
    int coef, exp;
    for (int i = 0; i < n; i++)
    {
        printf("请输入第%d项的系数和指数：", i + 1);
        scanf("%d%d", &coef, &exp);
        if (coef != 0)
        {
            Node* new_node = create_node(coef, exp);
            if (head == NULL)
            {
                head = new_node;
                tail = new_node;
            }
            else
            {
                tail->next = new_node;
                tail = new_node;
            }
        }
    }
    return head;
}

void print_poly(Node* head)
{
    Node* p = head;
    if (p == NULL)
    {
        printf("0\n");
    }
    else
    {
        printf("%dx^%d", p->coef, p->exp);
        p = p->next;
        while (p != NULL)
        {
            printf(" + %dx^%d", p->coef, p->exp);
            p = p->next;
        }
        printf("\n");
    }
}

Node* poly_mult(Node* poly1, Node* poly2)
{
    Node* result = NULL;
    Node* p1 = poly1;
    while (p1 != NULL)
    {
        Node* p2 = poly2;
        while (p2 != NULL)
        {
            int coef = p1->coef * p2->coef;
            int exp = p1->exp + p2->exp;
            Node* q = result;
            while (q != NULL && q->exp > exp)
            {
                q = q->next;
            }
            if (q == NULL)
            {
                Node* new_node = create_node(coef, exp);
                new_node->next = result;
                result = new_node;
            }
            else if (q->exp == exp)
            {
                q->coef += coef;
            }
            else
            {
                Node* new_node = create_node(coef, exp);
                new_node->next = q->next;
                q->next = new_node;
            }
            p2 = p2->next;
        }
        p1 = p1->next;
    }
    return result;
}

int main()
{
    int n1, n2;
    printf("请输入第一个多项式的项数：");
    scanf("%d", &n1);
    Node* poly1 = create_poly(n1);
    printf("第一个多项式为：");
    print_poly(poly1);
    printf("请输入第二个多项式的项数：");
    scanf("%d", &n2);
    Node* poly2 = create_poly(n2);
    printf("第二个多项式为：");
    print_poly(poly2);
    Node* result = poly_mult(poly1, poly2);
    printf("乘积为：");
    print_poly(result);
    return 0;
}