怎么在这个程序的基础上实现删除某个结点

#include
#include

typedef struct Node *NodePtr;
struct Node{
int Val;
NodePtr Next;
};

int main()
{
int N, M;
int i;
NodePtr Head, Rear, Pre, Tmp;

Head = Rear = (NodePtr)malloc(sizeof(struct Node));
Head->Next = NULL;

scanf("%d %d", &N, &M);
for(i=0;ire->Next = NULL;
    scanf("%d", &Pre->Val);
    Rear->Next=Pre; 
    Rear = Pre;
}

Pre = Head; 
while( Pre->Next != NULL && Pre->Next->Valre = Pre->Next;    
Tmp = (NodePtr)malloc(sizeof(struct Node));     
Tmp->Val = M;
Tmp->Next =Pre->Next; 
Pre->Next=Tmp;
if(Pre == Rear) 
    Rear = Tmp;
Tmp = Head->Next;
printf("%d", Tmp->Val);
for( Tmp=Tmp->Next; Tmp!= NULL; Tmp=Tmp->Next)    
    printf(" %d", Tmp->Val);
printf("\n");



return 0;

}