一元多项式加减乘除c语言

以下是一元多项式加减乘除的C语言代码实现：

一、一元多项式的结构体定义

typedef struct PolyNode *PtrToPoly;
struct PolyNode {
    int coef;   // 系数
    int expon;  // 指数
    PtrToPoly next;
};
typedef PtrToPoly Polynomial;

二、一元多项式的创建

Polynomial CreatePoly()
{
    Polynomial p, rear, t;
    int c, e, n;

    printf("请输入多项式的项数：");
    scanf("%d", &n);
    rear = (Polynomial)malloc(sizeof(struct PolyNode));
    rear->next = NULL;
    p = rear;

    while (n--) {
        printf("请输入系数和指数：");
        scanf("%d %d", &c, &e);
        t = (Polynomial)malloc(sizeof(struct PolyNode));
        t->coef = c;
        t->expon = e;
        t->next = NULL;
        rear->next = t;
        rear = t;
    }

    t = p;
    p = p->next;
    free(t);
    return p;
}

三、一元多项式的加法

Polynomial AddPoly(Polynomial p1, Polynomial p2)
{
    Polynomial front, rear, temp;
    int sum;

    rear = (Polynomial)malloc(sizeof(struct PolyNode));
    front = rear;

    while (p1 && p2) {
        if (p1->expon == p2->expon) {
            sum = p1->coef + p2->coef;
            if (sum) {
                temp = (Polynomial)malloc(sizeof(struct PolyNode));
                temp->coef = sum;
                temp->expon = p1->expon;
                rear->next = temp;
                rear = temp;
            }
            p1 = p1->next;
            p2 = p2->next;
        } else if (p1->expon > p2->expon) {
            temp = (Polynomial)malloc(sizeof(struct PolyNode));
            temp->coef = p1->coef;
            temp->expon = p1->expon;
            rear->next = temp;
            rear = temp;
            p1 = p1->next;
        } else {
            temp = (Polynomial)malloc(sizeof(struct PolyNode));
            temp->coef = p2->coef;
            temp->expon = p2->expon;
            rear->next = temp;
            rear = temp;
            p2 = p2->next;
        }
    }

    while (p1) {
        temp = (Polynomial)malloc(sizeof(struct PolyNode));
        temp->coef = p1->coef;
        temp->expon = p1->expon;
        rear->next = temp;
        rear = temp;
        p1 = p1->next;
    }

    while (p2) {
        temp = (Polynomial)malloc(sizeof(struct PolyNode));
        temp->coef = p2->coef;
        temp->expon = p2->expon;
        rear->next = temp;
        rear = temp;
        p2 = p2->next;
    }

    rear->next = NULL;
    temp = front;
    front = front->next;
    free(temp);
    return front;
}

四、一元多项式的减法

Polynomial SubtractPoly(Polynomial p1, Polynomial p2)
{
    Polynomial front, rear, temp;
    int sum;

    rear = (Polynomial)malloc(sizeof(struct PolyNode));
    front = rear;

    while (p1 && p2) {
        if (p1->expon == p2->expon) {
            sum = p1->coef - p2->coef;
            if (sum) {
                temp = (Polynomial)malloc(sizeof(struct PolyNode));
                temp->coef = sum;
                temp->expon = p1->expon;
                rear->next = temp;
                rear = temp;
            }
            p1 = p1->next;
            p2 = p2->next;
        } else if (p1->expon > p2->expon) {
            temp = (Polynomial)malloc(sizeof(struct PolyNode));
            temp->coef = p1->coef;
            temp->expon = p1->expon;
            rear->next = temp;
            rear = temp;
            p1 = p1->next;
        } else {
            temp = (Polynomial)malloc(sizeof(struct PolyNode));
            temp->coef = -p2->coef;
            temp->expon = p2->expon;
            rear->next = temp;
            rear = temp;
            p2 = p2->next;
        }
    }

    while (p1) {
        temp = (Polynomial)malloc(sizeof(struct PolyNode));
        temp->coef = p1->coef;
        temp->expon = p1->expon;
        rear->next = temp;
        rear = temp;
        p1 = p1->next;
    }

    while (p2) {
        temp = (Polynomial)malloc(sizeof(struct PolyNode));
        temp->coef = -p2->coef;
        temp->expon = p2->expon;
        rear->next = temp;
        rear = temp;
        p2 = p2->next;
    }

    rear->next = NULL;
    temp = front;
    front = front->next;
    free(temp);
    return front;
}

五、一元多项式的乘法

Polynomial MultiplyPoly(Polynomial p1, Polynomial p2)
{
    Polynomial p, rear, t, t1, t2;
    int c, e;

    if (!p1 || !p2) {
        return NULL;
    }

    t1 = p1;
    t2 = p2;
    rear = (Polynomial)malloc(sizeof(struct PolyNode));
    rear->next = NULL;
    p = rear;

    while (t2) {
        c = t1->coef * t2->coef;
        e = t1->expon + t2->expon;
        t = (Polynomial)malloc(sizeof(struct PolyNode));
        t->coef = c;
        t->expon = e;
        rear->next = t;
        rear = t;
        t2 = t2->next;
    }

    t1 = t1->next;

    while (t1) {
        t2 = p2;
        rear = p;

        while (t2) {
            e = t1->expon + t2->expon;
            c = t1->coef * t2->coef;

            while (rear->next && rear->next->expon > e) {
                rear = rear->next;
            }

            if (rear->next && rear->next->expon == e) {
                if (rear->next->coef + c) {
                    rear->next->coef += c;
                } else {
                    t = rear->next;
                    rear->next = t->next;
                    free(t);
                }
            } else {
                t = (Polynomial)malloc(sizeof(struct PolyNode));
                t->coef = c;
                t->expon = e;
                t->next = rear->next;
                rear->next = t;
                rear = rear->next;
            }

            t2 = t2->next;
        }

        t1 = t1->next;
    }

    t2 = p;
    p = p->next;
    free(t2);
    return p;
}

六、一元多项式的除法

void DividePoly(Polynomial dividend, Polynomial divisor, Polynomial *pQuotient, Polynomial *pRemainder)
{
    Polynomial temp;

    if (!divisor) {
        printf("除数不能为0！\n");
        return;
    }

    *pQuotient = (Polynomial)malloc(sizeof(struct PolyNode));
    (*pQuotient)->next = NULL;
    *pRemainder = (Polynomial)malloc(sizeof(struct PolyNode));
    (*pRemainder)->next = NULL;

    while (dividend && dividend->expon >= divisor->expon) {
        temp = (Polynomial)malloc(sizeof(struct PolyNode));
        temp->coef = dividend->coef / divisor->coef;
        temp->expon = dividend->expon - divisor->expon;
        temp->next = (*pQuotient)->next;
        (*pQuotient)->next = temp;

        temp = (Polynomial)malloc(sizeof(struct PolyNode));
        temp->coef = dividend->coef - temp->coef * divisor->coef;
        temp->expon = dividend->expon;
        temp->next = (*pRemainder)->next;
        (*pRemainder)->next = temp;

        dividend = dividend->next;
    }

    while (dividend) {
        temp = (Polynomial)malloc(sizeof(struct PolyNode));
        temp->coef = dividend->coef;
        temp->expon = dividend->expon;
        temp->next = (*pRemainder)->next;
        (*pRemainder)->next = temp;
        dividend = dividend->next;
    }

    temp = (*pQuotient);
    (*pQuotient) = (*pQuotient)->next;
    free(temp);

    temp = (*pRemainder);
    (*pRemainder) = (*pRemainder)->next;
    free(temp);
}