唐山市交警队:c语言问题

#include "stdio.h"
#include "conio.h"
#define LEN sizeof(struct danci)
struct danci
{
struct danci *next;
char name[20];
int flag; /*0代表符号，1代表字母*/
int c;/*0代表非字母，1代表奇数字母，2代表偶数字母*/
};
main()
{
char ch='0',a[100],b[20];
int n=0,j,i,m,k;
struct danci *head,*pf,*pb;
printf("please input your sentence:\n");
while(ch!='\n')
{
ch=getchar();
a[n]=ch;
n++;
}

pb=(struct danci*)malloc(LEN);
pf=head=pb;
for(m=0;m<=n;m++)
{
if(a[m]=='\0')
{k=0;
if (a[m+1]!=' ')
{
pf=pb;
pb=(struct danci*)malloc(LEN);
pf->next=pb;
}
if(a[m+1]>'A'&&a[m+1]<' ')
{
pb->flag=0;
pb->c=pf->c;
}
else

{
pb->flag=1;
if(pf->c==1)
pb->c=2;
else pb->c=1;
}
}
else

{
if(k==0)
pb->name[k]=a[m];
else pb->name[k]=a[m];
k=k+1;

}

}
pb->next=NULL;
pb=pf=head;
while(pb->next!=NULL)
{if (pb->flag==0)
printf("%c",pb->name);
pf=pb;
pb=pb->next;
if(pb->c==1)
{
if(pf->flag==0)
printf("%c",pb->name);
else
printf(" %c",pb->name);

}
else {
k=0;
while(pb->name[k]!=NULL)
{
k=k+1;
}
for(j=k-1;j>0;j--)
printf("%c",pb->name[j]);
}
}
getchar();
getchar();

}