最短路径问题 HDU1874

我知道代码长，想知道错哪了，实在没办法才扔代码问的。

#include<stdio.h>
#include<stdlib.h>
struct dian
{
int pos;
int dis;
struct dian* pnext;
};
void addlist(struct dian* head,int pos,int dis);
int findmin(struct dian* head,int town1,int town2,int N);
void freeall(struct dian* head,int N);
int main()
{
struct dian* head;
int x;
int N,M;
int S,T;
int ans;
for(;scanf("%d %d",&N,&M)!=EOF;)
{
head=(struct dian*)malloc(sizeof(struct dian)*N);
for(x=0;x<=N-1;x++)
{
head[x].pnext=NULL;
}
for(;M--;)
{
int A,B,X;
scanf("%d %d %d",&A,&B,&X);
addlist(&head[A],B,X);
addlist(&head[B],A,X);
}
scanf("%d %d",&S,&T);
ans=findmin(head,S,T,N);
if(ans!=99999)
{
printf("%d\n",ans);
}
else
{
printf("-1\n");
}
freeall(head,N);
}
return 0;
}
void addlist(struct dian* phead,int position,int distant)
{
struct dian* p=phead;
for(;p->pnext!=NULL;)
{
p=p->pnext;
}
p->pnext=(struct dian*)malloc(sizeof(struct dian));
p=p->pnext;
p->pos=position;
p->dis=distant;
p->pnext=NULL;
}
int findmin(struct dian* head,int town1,int town2,int N)
{
int *D,*H;
int x,j;
D=(int*)malloc(sizeof(int)*N);
H=(int*)malloc(sizeof(int)*N);
for(x=0;x<=N-1;x++)
{
D[x]=99999;
H[x]=-1;
}
D[town1]=0;
for(j=0;H[N-1]==-1;j++)
{
int i,min=0;
struct dian* p;
for(;H[min]!=-1;)
{
min++;
}
for(i=0;i<=N-1;i++)
{
if(D[min]>D[i]&&H[i]==-1)
{
min=i;
}
}
H[j]=min;
p=head[min].pnext;
for(;p!=NULL;)
{
if(p->dis+D[min]<D[p->pos])
{
D[p->pos]=p->dis+D[min];
}
p=p->pnext;
}
}
return D[town2];
}
void freeall(struct dian* head,int N)
{
int x;
for(x=0;x<=N-1;x++)
{
struct dian* p;
p=head[x].pnext;
for(;p!=NULL;)
{
struct dian* temp=p->pnext;
free(p);
p=temp;
}
head[x].pnext=NULL;
}
free(head);
}