check_stack2.c

fgdgyh trtrh rrt ertge e er er

#include<stdio.h>
//#include<string.h>
#include<stdlib.h>
#define OK 1
#define TRUE 1
#define FALSE 0
#define ERROR 0
#define OVERFLOW -2
#define STACK_INIF_SIZE 50
#define STACKINCREMENT 10
typedef int status;
typedef struct sqstack{
	int *base;
	int *top;
	int stacksize;
	}sqstack;
status *initstack(sqstack *s){
	(s)->base = (int*)malloc(STACK_INIF_SIZE*sizeof(int));
	if((s)->base==NULL) exit(OVERFLOW);
	(s)->top=(s)->base;
	(s)->stacksize = STACK_INIF_SIZE;
	printf("initstack is finished!\n");
	return OK;	
	}
int gettop(sqstack *s){
		int e;
		if(s->top==s->base){
			 printf("NULL1\n");
			 return 0;
			 }
		e=*(s->top-1);
		printf("gettop %d is OK!\n",e);
		return e;
		}
status push(sqstack *s,int e){
	if(s->top-s->base>=s->stacksize){
		s->base=(int*)realloc(s->base,(s->stacksize+STACKINCREMENT)*sizeof(int));
		if(!s->base) exit(OVERFLOW);
		s->stacksize+= STACKINCREMENT;
		}
	*(s->top++)=e;
    printf("push %d is OK\n",e);
	return OK;
	}
status pop(sqstack *s,int *e){
	if(s->top==s->base){
		printf("NULL2\n");
		return ERROR;
		}
	*e=*(--(s->top));
    printf("pop %d is OK!\n",*e);
	return OK;
	}
void main(){
	int b,e;
	char a='a',ch;
	sqstack s;
	initstack(&s);
	push(&s,a);
	b=gettop(&s);
	pop(&s,&e);
	printf("b is %d\n",b);
	ch=a;
	printf("%c\n",ch);
	
}