单链表实现一元多项式乘法与加法运算（C语言）

#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<stdlib.h>
struct Node
{
    int Coefficient;//多项式系数
    int Exponent;//指数2
    struct Node* Next;
};
typedef struct Node* nodePtr;
typedef nodePtr Polynomial;

Polynomial WritePoly();
void PrintPoly( Polynomial poly);
Polynomial AddPoly(Polynomial poly_1, Polynomial poly_2);
Polynomial MultPoly(Polynomial poly_1, Polynomial poly_2);
nodePtr Insert(int coefficient, int exponent, nodePtr position);
void freePoly(Polynomial poly);


int main(void)
{
    Polynomial Poly_1 = WritePoly();
    Polynomial Poly_2 = WritePoly();

    PrintPoly(MultPoly(Poly_1, Poly_2));
    PrintPoly(AddPoly(Poly_1,Poly_2));
    freePoly(Poly_1);
    freePoly(Poly_2);
    return 0;
}
nodePtr Insert(int coefficient, int exponent, nodePtr position)
{
    nodePtr insert = (nodePtr)malloc(sizeof(struct Node));
    if (insert != NULL)
    {
        insert->Coefficient = coefficient;
        insert->Exponent = exponent;
        insert->Next = position->Next;
        position->Next = insert;
    }
    return insert;
}
Polynomial WritePoly()
{
    Polynomial Poly = (Polynomial)malloc(sizeof(struct Node));
    if (Poly != NULL)
    {
        Poly->Next = NULL;
        nodePtr end = Poly;//设立尾结点
        int item;//多项式的项数
        scanf("%d", &item);
        //如果多项式项数等于0，那么就不输入信息
        if (item != 0)
        {
            for (int i = 0; i < item; i++)
            {
                Polynomial tmp = (Polynomial)malloc(sizeof(struct Node));
                if (tmp != NULL)
                {
                    scanf("%d %d", &(tmp->Coefficient), &(tmp->Exponent));
                    end->Next = tmp;
                    end = tmp;
                }
            }
            end->Next = NULL;
        }
    }
    return Poly;
}
void PrintPoly(Polynomial poly)
{
    if (poly != NULL)
    {
        Polynomial P = poly->Next;
        if (P != NULL)//当多项式项数不为0时
        {
            printf("%d %d", P->Coefficient, P->Exponent);
            P = P->Next;
            while (P != NULL)
            {
                printf(" %d %d", P->Coefficient, P->Exponent);
                P = P->Next;
            }
        }
        else
        {
            printf("0 0");
        }
        printf("
");
    }
    freePoly(poly);
}
Polynomial AddPoly(Polynomial poly_1,Polynomial poly_2)
{
    Polynomial resultPoly = (Polynomial)malloc(sizeof(struct Node));
    if (resultPoly != NULL)
    {
        resultPoly->Next = NULL;
        Polynomial curPoly1 = poly_1->Next;
        Polynomial curPoly2 = poly_2->Next;
        Polynomial lastPoly = resultPoly;
        while (curPoly1 != NULL && curPoly2 != NULL)
        {
            if (curPoly1->Exponent != curPoly2->Exponent)
            {
                nodePtr ins = curPoly1->Exponent > curPoly2->Exponent ? curPoly1 : curPoly2;
                lastPoly = Insert(ins->Coefficient, ins->Exponent, lastPoly);
                if (ins == curPoly1)
                {
                    curPoly1 = curPoly1->Next;
                }
                else
                {
                    curPoly2 = curPoly2->Next;
                }
            }
            else
            {
                int sumCoef = curPoly1->Coefficient + curPoly2->Coefficient;
                if (sumCoef != 0)
                {
                    lastPoly = Insert(sumCoef, curPoly1->Exponent, lastPoly);
                }
                curPoly1 = curPoly1->Next;
                curPoly2 = curPoly2->Next;
            }
        }
        Polynomial waitingforInsert = NULL;
        if (curPoly1 != NULL || curPoly2 != NULL)
        {
            waitingforInsert = (curPoly1 == NULL) ? curPoly2 : curPoly1;
        }
        else//curPoly1 = NULL && curPoly2 = NULL
        {
            waitingforInsert = NULL;
        }
        while (waitingforInsert != NULL)
        {
            lastPoly = Insert(waitingforInsert->Coefficient, waitingforInsert->Exponent, lastPoly);
            waitingforInsert = waitingforInsert->Next;
        }
        lastPoly->Next = NULL;
    }
    return resultPoly;
}
Polynomial MultPoly(Polynomial poly_1, Polynomial poly_2)
{
    Polynomial resultPoly = (Polynomial)malloc(sizeof(struct Node));
    if (resultPoly != NULL)
    {
        resultPoly->Next = NULL;
        Polynomial curPoly1 = poly_1->Next;
        Polynomial curPoly2 = poly_2->Next;
        Polynomial lastPoly = resultPoly;
        while (curPoly1 != NULL)
        {
            Polynomial polyTmp = (Polynomial)malloc(sizeof(struct Node));
            if (polyTmp != NULL)
            {
                nodePtr ins = polyTmp;
                polyTmp->Next = NULL;
                curPoly2 = poly_2->Next;
                while (curPoly2 != NULL)
                {
                    int newCoef = curPoly1->Coefficient * curPoly2->Coefficient;
                    int newExpo = curPoly1->Exponent + curPoly2->Exponent;
                    ins = Insert(newCoef, newExpo, ins);
                    curPoly2 = curPoly2->Next;
                }
                ins->Next = NULL;
            }
            resultPoly = AddPoly(polyTmp, resultPoly);
            freePoly(polyTmp);
            curPoly1 = curPoly1->Next;
        }
        lastPoly->Next = NULL;
    }
    return resultPoly;
}
void freePoly(Polynomial poly)
{
    nodePtr P = poly;
    nodePtr tmp;
    while (P != NULL)
    {
        tmp = P->Next;
        free(P);
        P = tmp;
    }
}