内存引用无效的问题

智能

#include <stdio.h> 
#include <stdlib.h> 
typedef struct node 
{ int coef, exp; 
struct node *next; 
} NODE; 

void multiplication( NODE *, NODE * , NODE * ); 
void input( NODE * ); 
void output( NODE * ); 
void multiplication(NODE*a,NODE*b,NODE*c)
{
NODE *a0=a;
NODE *b0=b;
NODE *c0=c;
NODE *c1=NULL;
NODE *lin=NULL;
NODE *zhong=NULL;
int ji,p=8,k;
while(b0->next!=NULL)
{
b0=b0->next;
a0=a;
while(a0->next!=NULL)
{
a0=a0->next;
ji=a0->coef*b0->coef;
k=a0->exp+b0->exp;
c0=c;
while(c0->next!=NULL)
{
p=0;
lin=c0;//临时存储c0 
c0=c0->next;
if(c0->exp>=k)
{p=1;break;}
}
if(c0->next==NULL&&p!=1)
{
if(c0->exp!=k)
{
zhong=(NODE*)malloc(sizeof(NODE));
c0->next=zhong;
zhong->next=NULL;
zhong->coef=ji;
zhong->exp=k;
}
else
c0->coef=c0->coef+ji; 
} 
if(c0->exp==k)
{
c0->coef=c0->coef+ji;
}
if(c0->exp>k)
{
c1=(NODE*)malloc(sizeof(NODE));//新申请c1
lin->next=c1;
c1->next=c0;
c1->exp=k;
c1->coef=ji;
}
}
}
} 



void input( NODE * head ) 
{ int flag, sign, sum, x; 
char c; 

NODE * p = head; 

while ( (c=getchar()) !='\n' ) 
{ 
if ( c == '<' ) 
{ sum = 0; 
sign = 1; 
flag = 1; 
} 
else if ( c =='-' ) 
sign = -1; 
else if( c >='0'&& c <='9' ) 
{ sum = sum*10 + c - '0'; 
} 
else if ( c == ',' ) 
{ if ( flag == 1 ) 
{ x = sign * sum; 
sum = 0; 
flag = 2; 
sign = 1; 
} 
} 
else if ( c == '>' ) 
{ p->next = ( NODE * ) malloc( sizeof(NODE) ); 
p->next->coef = x; 
p->next->exp = sign * sum; 
p = p->next; 
p->next = NULL; 
flag = 0; 
} 
} 
} 

void output( NODE * head ) 
{ 
while ( head->next != NULL ) 
{ head = head->next; 
printf("<%d,%d>,", head->coef, head->exp ); 
} 
printf("\n"); 
} 
int main() 
{ NODE * head1, * head2, * head3; 

head1 = ( NODE * ) malloc( sizeof(NODE) ); 
input( head1 ); 

head2 = ( NODE * ) malloc( sizeof(NODE) ); 
input( head2 ); 

head3 = ( NODE * ) malloc( sizeof(NODE) ); 
head3->next = NULL; 
multiplication( head1, head2, head3 ); 

output( head3 ); 
system("pause");

return 0; 
} 

用dev和vs都可以编译并输出正确结果，但用gcc会提示“无效内存引用。”其中multiplication函数是自己编的，其它是预制代码

智能

没人来吗。。。。。

智能

再次求解答