多项式相加

#include <stdio.h> 
#include <stdlib.h> 
 
typedef struct PolyNode *PtrToNode; 
 
//定义链表节点，也就是多项式中的某一项； 
typedef struct PolyNode 
{ 
    int Coeff; 
    int Exponent; 
    PtrToNode Next; 
} PolyNode; 
 
 
typedef PtrToNode Polynomial; 
 
/************************************************************ 
*多项式相加的函数: 
*P、Q为存储两个多项式各项的单链表(含头结点) 
*Sum为多项式相加结果存放的单链表 
* 
************************************************************/ 
void AddPolynomial(Polynomial P,Polynomial Q,Polynomial Sum) 
{ 
    Polynomial PIndex,QIndex,SumIndex; 
    PIndex = P->Next; 
    QIndex = Q->Next; 
    SumIndex = Sum; 
    while(!(PIndex == NULL && QIndex == NULL)) 
    { 
        if(PIndex==NULL) 
        { 
            SumIndex->Next = QIndex; 
            QIndex = QIndex->Next; 
            SumIndex = SumIndex->Next; 
        } 
        else if(QIndex == NULL) 
        { 
            SumIndex->Next = PIndex; 
            PIndex = PIndex->Next; 
            SumIndex = SumIndex->Next; 
        } 
        else 
        { 
            if(PIndex->Exponent > QIndex->Exponent) 
            { 
                SumIndex->Next = PIndex; 
                PIndex = PIndex->Next; 
                SumIndex = SumIndex->Next; 
                //continue在判断下面if条件时会有异常，类似Java 
                //的空引用异常 
                continue; 
            } 
            if(PIndex->Exponent == QIndex->Exponent) 
            { 
                Polynomial PP =(Polynomial) malloc(sizeof(struct PolyNode)); 
                PP->Exponent = PIndex->Exponent; 
                PP->Coeff = PIndex->Coeff + QIndex->Coeff; 
                SumIndex->Next = PP; 
                PIndex = PIndex->Next; 
                QIndex = QIndex->Next; 
                SumIndex = SumIndex->Next; 
                continue; 
            } 
            if(PIndex->Exponent < QIndex->Exponent) 
            { 
                SumIndex->Next = QIndex; 
                QIndex = QIndex->Next; 
                SumIndex = SumIndex->Next; 
                continue; 
            } 
        } 
    } 
    SumIndex->Next = NULL; 
} 
 
/************************************************************ 
*遍历单链表(含头结点)函数: 
*P：待遍历的链表 
*************************************************************/ 
void TraversePolynomial(Polynomial P) 
{ 
    Polynomial Tmp = P->Next; 
    while(Tmp != NULL) 
    { 
        printf("Coeff is %d and Exponent is %d\n",Tmp->Coeff,Tmp->Exponent); 
        Tmp = Tmp->Next; 
    } 
} 
 
 
 
int main( ) 
{ 
    Polynomial Poly1,Poly2,Poly3,Poly11,Poly22; 
    int i,j; 
    Poly1 =(Polynomial) malloc(sizeof(struct PolyNode)); 
    Poly2 =(Polynomial) malloc(sizeof(struct PolyNode)); 
    Poly3 =(Polynomial) malloc(sizeof(struct PolyNode)); 
    Poly11 = Poly1; 
    Poly22 = Poly2; 
 
    //创建两个链表时，需要保证是按照指数递减的方式构造的 
    for(i = 5;i >= 1;i--) 
    { 
        Polynomial Tmp  =(Polynomial) malloc(sizeof(struct PolyNode)); 
        Tmp->Coeff = i; 
        Tmp->Exponent = i; 
        Poly11->Next = Tmp; 
        Poly11 = Poly11->Next; 
    } 
    Poly11->Next = NULL; 
    for(j = 11;j >= 3;j--) 
    { 
        Polynomial Tmp  =(Polynomial) malloc(sizeof(struct PolyNode)); 
        Tmp->Coeff = j; 
        Tmp->Exponent = j; 
        Poly22->Next = Tmp; 
        Poly22 = Poly22->Next; 
    } 
    Poly22->Next = NULL; 
    TraversePolynomial(Poly1); 
    printf("*****************************************\n"); 
    TraversePolynomial(Poly2); 
    AddPolynomial(Poly1,Poly2,Poly3); 
    printf("*****************************************\n"); 
    TraversePolynomial(Poly3); 
    return 0; 
}