栈的数组实现
stackar.h
1 /* 栈的数组实现的类型声明*/ 2 3 typedef int ElementType; 4 /* START: fig3_45.txt */ 5 #ifndef _Stack_h 6 #define _Stack_h 7 8 struct StackRecord; 9 typedef struct StackRecord *Stack; 10 11 int IsEmpty( Stack S ); 12 int IsFull( Stack S ); 13 Stack CreateStack( int MaxElements ); 14 void DisposeStack( Stack S ); 15 void MakeEmpty( Stack S ); 16 void Push( ElementType X, Stack S ); 17 ElementType Top( Stack S ); 18 void Pop( Stack S ); 19 ElementType TopAndPop( Stack S ); 20 21 #endif /* _Stack_h */ 22 23 /* END */
stackar.c
1 #include "stackar.h" 2 #include "fatal.h" 3 #include <stdlib.h> 4 5 #define EmptyTOS ( -1 ) 6 #define MinStackSize ( 5 ) 7 8 struct StackRecord 9 { 10 int Capacity; 11 int TopOfStack; 12 ElementType *Array; 13 }; 14 15 /* START: fig3_48.txt */ 16 17 /* 判断栈是否为空 */ 18 int 19 IsEmpty( Stack S ) 20 { 21 return S->TopOfStack == EmptyTOS; 22 } 23 /* END */ 24 25 /*判断栈是否满了 */ 26 int 27 IsFull( Stack S ) 28 { 29 return S->TopOfStack == S->Capacity - 1; 30 } 31 32 /* START: fig3_46.txt */ 33 34 /* 创建一个空栈 */ 35 Stack 36 CreateStack( int MaxElements ) 37 { 38 Stack S; 39 40 /* 1*/ if( MaxElements < MinStackSize ) 41 /* 2*/ Error( "Stack size is too small" ); 42 43 /* 3*/ S = malloc( sizeof( struct StackRecord ) ); 44 /* 4*/ if( S == NULL ) 45 /* 5*/ FatalError( "Out of space!!!" ); 46 47 /* 6*/ S->Array = malloc( sizeof( ElementType ) * MaxElements ); 48 /* 7*/ if( S->Array == NULL ) 49 /* 8*/ FatalError( "Out of space!!!" ); 50 /* 9*/ S->Capacity = MaxElements; 51 /*10*/ MakeEmpty( S ); 52 53 /*11*/ return S; 54 } 55 /* END */ 56 57 /* START: fig3_49.txt */ 58 59 /* 使栈顶指向-1,即空栈 */ 60 void 61 MakeEmpty( Stack S ) 62 { 63 S->TopOfStack = EmptyTOS; 64 } 65 /* END */ 66 67 /* START: fig3_47.txt */ 68 69 /* 释放栈 */ 70 void 71 DisposeStack( Stack S ) 72 { 73 if( S != NULL ) 74 { 75 free( S->Array ); 76 free( S ); 77 } 78 } 79 /* END */ 80 81 /* START: fig3_50.txt */ 82 83 /* 入栈 */ 84 void 85 Push( ElementType X, Stack S ) 86 { 87 if( IsFull( S ) ) 88 Error( "Full stack" ); 89 else 90 S->Array[ ++S->TopOfStack ] = X; 91 } 92 /* END */ 93 94 95 /* START: fig3_51.txt */ 96 97 /* 返回栈顶元素 */ 98 ElementType 99 Top( Stack S ) 100 { 101 if( !IsEmpty( S ) ) 102 return S->Array[ S->TopOfStack ]; 103 Error( "Empty stack" ); 104 return 0; /* Return value used to avoid warning */ 105 } 106 /* END */ 107 108 /* START: fig3_52.txt */ 109 110 /* 出栈 */ 111 void 112 Pop( Stack S ) 113 { 114 if( IsEmpty( S ) ) 115 Error( "Empty stack" ); 116 else 117 S->TopOfStack--; 118 } 119 /* END */ 120 121 /* START: fig3_53.txt */ 122 123 /* 返回栈顶元素和出栈 */ 124 ElementType 125 TopAndPop( Stack S ) 126 { 127 if( !IsEmpty( S ) ) 128 return S->Array[ S->TopOfStack-- ]; 129 Error( "Empty stack" ); 130 return 0; /* Return value used to avoid warning */ 131 } 132 /* END */