栈的实现
include <stdio.h>
include <stdlib.h>
define STACK_INIT_SIZE 100
define INCRE 10
define ERROR -1
define OK 1
typedef struct{
int *base;
int *top;
int stacksize;
}SqStack;
int InitStack(SqStack *S){
S->base = (int *)malloc(STACK_INIT_SIZE * sizeof(int));
if(!S->base) return ERROR;
S->top = S->base;
S->stacksize = STACK_INIT_SIZE;
return OK;
}
int Print(SqStack S){
int *i = S.top;
if(S.base == S.top)
return ERROR;
while(i > S.base){
i--;
printf("%d ", *i);
}
putchar('\n');
return OK;
}
void CreadStack(SqStack S, int n){
printf("请输入%d个元素:", n);
int i = 0;
while(i < n){
scanf("%d", S->top);
S->top++;
i++;
}
Print(S);
}
int GetTop(SqStack *S, int num){
if(S->base == S->top)
return ERROR;
num = *(S->top-1);
printf("top: %d\n", num);
return OK;
}
int Push(SqStack *S, int num){
if(S->top - S->base >= S->stacksize){
S->base = (int )realloc(S->base, (S->stacksize+INCRE)sizeof(int));
if(!S->base){
return ERROR;
}
S->top = S->base + S->stacksize;
S->stacksize += INCRE;
}
(S->top++) = num;
Print(S);
return OK;
}
int Pop(SqStack *S, int num){
if(S->top == S->base){
return ERROR;
}
num = --S->top;
printf("Pop:%d\n", num);
Print(S);
return OK;
}
int Show(){
int n;
printf("*****************\n");
printf("1、获取栈顶元素。\n");
printf("2、插入元素。\n");
printf("3、删除栈顶元素。\n");
printf("4、退出。\n");
printf("-----------------\n");
printf("请选择要操作的序号:");
scanf("%d", &n);
return n;
}
int main()
{
SqStack S;
int num = 0;
InitStack(&S);
CreadStack(&S, 5);
int sele = Show();
while(sele != 4){
switch(sele){
case 1:
GetTop(&S, num);
sele = Show();
break;
case 2:
printf("请输入要进栈的数字:");
scanf("%d", &num);
Push(&S, num);
sele = Show();
break;
case 3:
Pop(&S, num);
sele = Show();
break;
case 4:
break;
}
}
return 0;
}