堆栈的C代码实现

2009-09-13     16:42:43  

 

 今天实现堆栈结构部分的代码，并用一简单程序测试成功。

 

stack.h:

 

#ifndef _STACK_H_ #define _STACK_H_ #include <stdio.h> #include <stdlib.h> #include <memory.h> #define STACK_INIT_SIZE 5 #define STACKINCREMENT 5 typedef int SElemType; //the elements type typedef enum { TRUE=0, FALSE=-1 } Status; typedef struct { SElemType *base; SElemType *top; int stacksize; }SqStack; Status InitStack(SqStack *S); Status DestoryStack(SqStack *S); Status ClearStack(SqStack *S); Status StackEmpty(SqStack S); int LengthStack(SqStack S); Status GetTop(SqStack S,SElemType *e); Status Push(SqStack *S,SElemType e); Status Pop(SqStack *S,SElemType *e); Status StackTraverse(SqStack S); #endif

 

stack.c

 

#include "Stack.h" Status InitStack (SqStack *S) { if((S->base=(SElemType *)malloc(STACK_INIT_SIZE * sizeof(SElemType)))==(SElemType*)NULL){ printf("init stack malloc error !/n"); return FALSE; } S->top=S->base; S->stacksize=STACK_INIT_SIZE; return TRUE; } Status DestoryStack(SqStack* S) { free(S->base); S->base=S->top=(SElemType*)NULL; S->stacksize=0; return TRUE; } Status ClearStack(SqStack * S) { if(S->top <= S->base){ printf("not stack or empty stack !/n"); return FALSE; } S->top = S->base; return FALSE; } Status StackEmpty(SqStack S) { if(S.top == S.base){ printf("empty stack checked!/n"); return TRUE; } else return FALSE; } int LengthStack(SqStack S) { return S.top-S.base; } Status GetTop(SqStack S, SElemType * e) { if(S.top==S.base){ printf("the stack is already empty !/n"); return FALSE; } *e=*(S.top-1); return TRUE; } Status StackRealloc (SqStack *S, size_t size) { size_t offset = 0; SElemType* temp = (SElemType *)NULL; if((temp = (SElemType*)malloc(size))==(SElemType*)NULL){ printf("realloc address OX%d/n"); printf("realloc error!/n"); return FALSE; } offset = S->top-S->base; memcpy(temp,S->base,offset*sizeof(SElemType)); S->stacksize += STACKINCREMENT; free(S->base); S->base = temp; S->top = S->base+offset; return TRUE; } Status Push(SqStack * S, SElemType e) { if(S->top - S->base >= (S->stacksize-1)){ printf("stack full,realloc memory now!/n"); if(( StackRealloc(S,(size_t)(S->stacksize+STACKINCREMENT)*sizeof(SElemType))) == FALSE) { //printf("realloc memory error !/n"); return FALSE; } else printf("realloc memory ok!/n"); } *(*S).top = e; S->top ++; return TRUE; } Status Pop(SqStack * S, SElemType * e){ if(S->top == S->base){ printf("aleady reach stack bottom!/n"); return FALSE; } *e = *--S->top; return TRUE; } Status StackTraverse(SqStack S){ SElemType *flag; if(S.base == S.top){ printf("empty stack !/n"); return FALSE; } if(S.base > S.top){ printf("stack error,need rebuild!/n"); return FALSE; } for (flag = S.base;flag<S.top;flag++){ printf("[%d]",(int)*flag); } printf("/n travel over!/n"); return TRUE; }

 

stacktest.c (堆栈函数库调用测试)：

 

#include "Stack.h" int main() { int i=0;int length=0; SqStack stack1={(SElemType*)NULL,(SElemType*)NULL,0}; printf("how long stack will you test ? :"); scanf("%d",&length); printf("the length is %d",length); if(InitStack(&stack1) == FALSE){ printf("INIT error!/n"); return -1; } printf("stack1= {%d,%d,%d}/n",stack1.base,stack1.top,stack1.stacksize); StackTraverse(stack1); for(i=0;i<length;i++){ Push(&stack1, i); } StackTraverse(stack1); return 0; }

 

该函数库实现堆栈的初始化，PUSH和POP操作（PUSH时空间不够会自动分配新空间，但是只实现了动态分配内存，没有考虑对过于频繁的操作下产生的内存碎片的处理，一次性分配教大的STACKSIZE可以缓解），栈空检测及遍历栈的操作。

测试程序，通过对栈先PUSH进比初始大小更多的元素值然后遍历所有元素来检测大部分的函数功能。