数据结构学习第二天

 1 #ifndef _LIST_H
 2 #define _LIST_H
 3 #define len sizeof(Node)
 4 struct Node;
 5 typedef struct Node* PtrToNode;
 6 typedef PtrToNode List;
 7 typedef PtrToNode Position;
 8 List MakeEmety(List L);
 9 int IsEmpty(List L);
10 int IsLast(Position P, List L);
11 Position Find(int Element, List L);
12 void Delete(int Element, List L);
13 Position FindPrevious(int Element, List L);
14 void Insert(int Element, List L, Position P);
15 void DeleteList(List L);
16 Position Header(List L);
17 Position First(List L);
18 
19 #endif // !_LIST_H

 1 #include<malloc.h>
 2 #include "List.h"
 3 struct Node
 4 {
 5     int Element;
 6     Position Next;
 7 };
 8 List MakeEmety(List L)
 9 {
10     List head = (List)malloc(len);
11     head->Next = NULL;
12     return head;
13 }
14 
15 int IsEmpty(List L)
16 {
17     return L->Next == NULL;
18 }
19 
20 int IsLast(Position P, List L)
21 {
22     return P->Next == NULL;
23 }
24 
25 Position Find(int Element, List L)
26 {
27     Position P = L->Next;
28     while (P!=NULL)
29     {
30         if (P->Element == Element)
31             return P;
32         else
33             P = P->Next;
34     }
35     return NULL;
36 }
37 
38 void Delete(int Element, List L)
39 {
40     Position P1, P2;
41     P1=P2= FindPrevious(Element,L);
42     P1->Next = P1->Next->Next;
43     free(P2);
44 }
45 
46 Position FindPrevious(int Element, List L)
47 {
48     Position P = L;
49     while (P ->Next!= NULL)
50     {
51         if (P->Next->Element == Element)
52             return P;
53         else
54             P = P->Next;
55     }
56     return NULL;
57 }
58 
59 void Insert(int Element, List L, Position P)
60 {
61     Position P1 = (Position)malloc(len);
62     P->Element = Element;
63     Position PreP = FindPrevious(P->Element,L);
64     P1->Next = P;
65     PreP->Next = P1;
66 }
67 
68 void DeleteList(List L)
69 {
70     Position P1, P2;
71     P1 = P2 = L;
72     while (P2!= NULL)
73     {
74         P2 = P1->Next;
75         free(P1);
76         P1 = P2;
77     }
78 }
79 
80 Position Header(List L)
81 {
82     return L;
83 }
84 
85 Position First(List L)
86 {
87     return L;
88 }