栈

  1 #include <stdio.h>
  2 #include <stdlib.h>
  3 
  4 typedef int ElementType;
  5 
  6 struct StackNode
  7 {
  8     ElementType Element;
  9     struct StackNode *Next;
 10 };
 11 
 12 int StackIsEmpty(struct StackNode *StackTop)
 13 {
 14     return (StackTop -> Next == NULL);
 15 }
 16 
 17 int StackPush(ElementType ToBePush,struct StackNode *StackTop)
 18 {
 19     struct StackNode *TmpCell;
 20     
 21     TmpCell = malloc(sizeof(struct StackNode));
 22     if(TmpCell == NULL)
 23     {
 24         return 1;
 25     }
 26     else
 27     {
 28         TmpCell -> Element = ToBePush;
 29         TmpCell -> Next = StackTop -> Next;
 30         StackTop -> Next = TmpCell;
 31     }
 32     return 0;
 33 }
 34 
 35 ElementType StackGetTop(struct StackNode *StackTop)
 36 {
 37     if(!StackIsEmpty(StackTop))
 38     {
 39         return StackTop -> Next -> Element;
 40     }
 41     
 42     return 1;
 43 }
 44 
 45 int StackPop(struct StackNode *StackTop)
 46 {
 47     struct StackNode *FirstCell;
 48     
 49     if(StackIsEmpty(StackTop))
 50     {
 51         return 1;
 52     }
 53     else
 54     {
 55         FirstCell = StackTop -> Next;
 56         StackTop -> Next = StackTop -> Next -> Next;
 57         free(FirstCell);
 58     }
 59     return 0;
 60 }
 61 
 62 int MakeStackEmpty(struct StackNode *StackTop)
 63 {
 64     if(StackTop == NULL)
 65     {
 66         return 1;
 67     }
 68     else
 69     {
 70         while( !StackIsEmpty(StackTop) )
 71         {
 72             StackPop(StackTop);
 73         }
 74     }
 75     return 0;
 76 }
 77 
 78 struct StackNode *StackInit()
 79 {
 80     struct StackNode *StackTop;
 81     
 82     StackTop = malloc(sizeof(struct StackNode));
 83     if(StackTop == NULL)
 84     {
 85         return NULL;
 86     }
 87         
 88     StackTop -> Next = NULL;
 89     MakeStackEmpty(StackTop);
 90     return StackTop;
 91 }
 92 
 93 int StackDelete(struct StackNode *StackTop)
 94 {
 95     if(StackTop == NULL)
 96     {
 97         return 1;
 98     }
 99     else
100     {
101         MakeStackEmpty(StackTop);
102         free(StackTop);
103     }
104     return 0;
105 }
106 
107 int main()
108 {
109     struct StackNode *StackTop;
110     StackTop = StackInit();
111     
112     StackPush(11,StackTop);
113     StackPush(12,StackTop);
114     StackPush(13,StackTop);
115     int TopEle = StackGetTop(StackTop);
116     printf("%d
",TopEle);
117     StackPop(StackTop);
118     TopEle = StackGetTop(StackTop);
119     printf("%d
",TopEle);
120     StackPop(StackTop);
121     StackPop(StackTop);
122     StackPop(StackTop);
123     StackPop(StackTop);
124     StackPop(StackTop);
125     StackPop(StackTop);
126     StackPop(StackTop);
127     StackPop(StackTop);
128     TopEle = StackGetTop(StackTop);
129     printf("%d
",TopEle);
130     MakeStackEmpty(StackTop);
131     StackPush(1,StackTop);
132     StackPush(2,StackTop);
133     StackPush(3,StackTop);
134     MakeStackEmpty(StackTop);
135     StackDelete(StackTop);
136     return 0;
137 }