用c语言链表实现多项式乘法

要用C语言链表实现多项式乘法，首先需要定义一个多项式的结构体，其中包含多项式的系数和指数。然后可以通过创建链表的方式存储多项式。

下面是一个示例代码，实现了多项式乘法的函数：

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

// 定义多项式节点结构体
typedef struct PolynomialNode {
    int coefficient;  // 系数
    int exponent;     // 指数
    struct PolynomialNode* next;  // 下一个节点指针
} PolynomialNode;

// 创建多项式节点
PolynomialNode* createNode(int coefficient, int exponent) {
    PolynomialNode* node = (PolynomialNode*)malloc(sizeof(PolynomialNode));
    node->coefficient = coefficient;
    node->exponent = exponent;
    node->next = NULL;
    return node;
}

// 在链表末尾插入节点
void insertNode(PolynomialNode** head, int coefficient, int exponent) {
    PolynomialNode* newNode = createNode(coefficient, exponent);
    if (*head == NULL) {
        *head = newNode;
    } else {
        PolynomialNode* curr = *head;
        while (curr->next != NULL) {
            curr = curr->next;
        }
        curr->next = newNode;
    }
}

// 打印多项式
void printPolynomial(PolynomialNode* head) {
    PolynomialNode* curr = head;
    while (curr != NULL) {
        printf("%dx^%d ", curr->coefficient, curr->exponent);
        curr = curr->next;
        if (curr != NULL) {
            printf("+ ");
        }
    }
    printf("\n");
}

// 多项式乘法
PolynomialNode* multiplyPolynomials(PolynomialNode* poly1, PolynomialNode* poly2) {
    PolynomialNode* result = NULL;

    PolynomialNode* curr1 = poly1;
    while (curr1 != NULL) {
        PolynomialNode* curr2 = poly2;
        while (curr2 != NULL) {
            int coefficient = curr1->coefficient * curr2->coefficient;
            int exponent = curr1->exponent + curr2->exponent;
            insertNode(&result, coefficient, exponent);
            curr2 = curr2->next;
        }
        curr1 = curr1->next;
    }

    return result;
}

// 释放链表内存
void freeList(PolynomialNode* head) {
    PolynomialNode* curr = head;
    while (head != NULL) {
        head = head->next;
        free(curr);
        curr = head;
    }
}

int main() {
    PolynomialNode* poly1 = NULL;
    PolynomialNode* poly2 = NULL;

    // 多项式1: 3x^2 + 4x^1 + 2x^0
    insertNode(&poly1, 3, 2);
    insertNode(&poly1, 4, 1);
    insertNode(&poly1, 2, 0);

    // 多项式2: 2x^2 + 5x^0
    insertNode(&poly2, 2, 2);
    insertNode(&poly2, 5, 0);

    printf("多项式1:");
    printPolynomial(poly1);

    printf("多项式2:");
    printPolynomial(poly2);

    PolynomialNode* result = multiplyPolynomials(poly1, poly2);
    printf("乘法结果:");
    printPolynomial(result);

    // 释放内存
    freeList(poly1);
    freeList(poly2);
    freeList(result);

    return 0;
}

运行上述代码，即可实现多项式的乘法。代码中通过创建链表的方式存储多项式，然后使用两重循环遍历两个链表，并将乘积的结果插入到一个新的链表中。最后打印新链表中的多项式结果。