编译器-C语言，编译和链接均未报错，运行时出现异常。

问题描述

C语言，编译和链接均未报错，运行时出现异常。

编译器报告异常信息(http://img.ask.csdn.net/upload/201508/30/1440920346_80190.png)

代码如下
#include
#include
#include
#define TRUE 1
#define FASLE 0
#define OK 1
#define ERROR 0
#define OVERFLOW -2
typedef int Status;
typedef struct elemType
{
float coef;
int expn;

}ElemType;
typedef struct polyn
{
ElemType e;
struct polyn *next;
}Polyn;

void initPolyn(Polyn *Pn);
Status initList(Polyn *Pn);
int listLength(Polyn Pn);
Status appendList(Polyn *Pn,ElemType e);

Status initList(Polyn *Pn)
{
Pn = (Polyn *)malloc(sizeof(Polyn));
Pn->next = NULL;
if(!Pn)
exit(OVERFLOW);
return OK;
}
int listLength(Polyn Pn)
{

Polyn *p = Pn.next;
int i = 0;
printf("function : the length of the PolynList!n");
printf("coef=%f,expn=%dn",Pn.next->e.coef,Pn.next->e.expn);
while(p!=NULL)
{
     i++;
     p = p->next;
}

return i;

}
Status appendList(Polyn *Pn,ElemType e)
{
Polyn *s = (Polyn *)malloc(sizeof(Polyn));
s->next = NULL;
s->e.coef = e.coef;
s->e.expn = e.expn;
s->next = Pn->next;
Pn->next = s;
return OK;

}
void initPolyn(Polyn *Pn)
{
ElemType e;
int i=0,n;
printf("请输入多项式Polyn的项数：");
scanf_s("%d",&n);
printf("请输入多项式Polyn的系数和指数，用逗号隔开！n");
for(i=0;i<n;i++)
{
scanf_s("%f,%d",&e.coef,&e.expn);
appendList(Pn,e);
}
}
void main()
{
Polyn Pn;

initList(&Pn);
initPolyn(&Pn);
printf("%dn",listLength(Pn));
system("pause");

}

解决方案

http://download.csdn.net/detail/nanshao3618/2879641

解决方案二：

initList(Pn);之后Pn还是NULL，想要在子函数改变指针要用2级指针。

解决方案三：

 #define TRUE 1
#define FASLE 0
#define OK 1
#define ERROR 0
#define OVERFLOW -2
typedef int Status;
typedef struct elemType
{
    float coef;
    int expn;
}ElemType;
typedef struct polyn
{
    ElemType e;
    struct polyn *next;
}Polyn;
void initPolyn(Polyn *Pn);
Status initList(Polyn **Pn);
int listLength(Polyn Pn);
Status appendList(Polyn *Pn,ElemType e);
Status initList(Polyn **Pn)
{
    *Pn = (Polyn *)malloc(sizeof(Polyn));
    (*Pn)->next = NULL;
    if(!Pn)
    exit(OVERFLOW);
    return OK;
}
int listLength(Polyn Pn)
{
    Polyn *p = Pn.next;
    int i = 0;
    printf("function : the length of the PolynList!n");
    printf("coef=%f,expn=%dn",Pn.next->e.coef,Pn.next->e.expn);
    while(p!=NULL)
    {
         i++;
         p = p->next;
    }

    return i;
}
Status appendList(Polyn *Pn,ElemType e)
{
    Polyn *s = (Polyn *)malloc(sizeof(Polyn));
    s->next = NULL;
    s->e.coef = e.coef;
    s->e.expn = e.expn;
    s->next = Pn->next;
    Pn->next = s;
    return OK;
}
void initPolyn(Polyn *Pn)
{
    ElemType e;
    int i=0,n;
    printf("请输入多项式Polyn的项数：");
    scanf_s("%d",&n);
    printf("请输入多项式Polyn的系数和指数，用逗号隔开！n");
    for(i=0;i<n;i++)
    {
        scanf_s("%f,%d",&e.coef,&e.expn);
        appendList(Pn,e);
    }
}
void main()
{
    Polyn *Pn;
    initList(&Pn);
    initPolyn(Pn);
    printf("%dn",listLength(*Pn));
    system("pause");
}

解决方案四：

我这边可以，你输入的是什么？