1. C的实现
//stack.h
#ifndef STACK_H
#define STACK_H
#define STACK_CAPACITY 20//maximum size of stack
typedef int stackEle;
typedef struct
{
stackEle myArray[ STACK_CAPACITY ];
int myTop;
}stack;
//construct(initialize) an empty stack
stack *stack_init(void);
//return 1 if stack is empty and 0 otherwise
int empty(stack *);
//retrieve top element of the stack
stackEle top(stack* );
//add an element at the top of the stack
void push(stack*,stackEle);
//remove the top element of the stack
void pop(stack* );
#endif
//stack.c
#include <stdio.h>
#include "stack.h"
#include <assert.h>
#include <stdlib.h>
//construct (initialize) an empty stack
stack* stack_init(void)
{
stack* s = (stack*)malloc(sizeof(stack));
assert(s);
s->myTop = -1;//stack is empty
return s;
}
//return 1 if stack is empty and 0 otherwise
int empty(stack *s)
{
assert(s);
if(0 > s->myTop)
return 1;
else
return 0;
}
//retrieve top element of the stack
stackEle top(stack* s)
{
assert(s);
if(0 > s->myTop)
{
printf("Error:stack is empty--no value can be reported\n");
exit(1);
}
return s->myArray[s->myTop];
}
//add an element at the top of the stack
void push(stack* s,stackEle val)
{
assert(s);
s->myTop++;
if(STACK_CAPACITY < s->myTop)//check if overflow
{
printf("Error:stack is full--can't add new value\n");
exit(1);
}
s->myArray[s->myTop] = val;
}
//remove the top element of the stack
void pop(stack* s)
{
assert(s);
if(0 > s->myTop)//check if underflow
{
printf("Error:stack is empty--can't remove a value\n");
exit(1);
}
printf("%d ",s->myArray[s->myTop--]);
}
//do base-10 to base-2 transformation by array-based stack
int main()
{
stack *mystack = stack_init();
int a = 255,b,base = 2;
do
{
b = a % base;
push(mystack,b);
a = a / base;
} while(a != 0);
while(!empty(mystack))
pop(mystack);
