#include "stdio.h"
#include "stdlib.h"
typedef int E;
struct Stack{
    E * array;
    int capacity;
    int top;
}; 
typedef struct Stack * ArrayStack;
int initStack(ArrayStack stack){
    stack->array = (E*)malloc(sizeof(E) * 10);
    if(stack->array == NULL) return 0;
    stack->capacity = 10;
    stack->top = -1;
    return 1;
}
int pushStack(ArrayStack stack,E element){
    if(stack->top+1==stack->capacity){
        int newCapacity = stack->capacity+(stack->capacity >> 1);
        E * newArray = (E*)realloc(stack->array,newCapacity*sizeof(E));
        if(newArray == NULL) return 0;
        stack->array = newArray;
        stack->capacity = newCapacity;
    }
    stack->array[stack->top+1] = element;
    stack->top++;
    return 1;
}
void printStack(ArrayStack stack){
    printf("| ");
    for (int i = 0; i < stack->top + 1; ++i) {
        printf("%d, ", stack->array[i]);
    }
    printf("\n");
}
int isEmpty(ArrayStack stack){
    return stack->top == -1;
}
int popStack(ArrayStack stack){
    return stack->array[stack->top--];
}
int main(){
    struct Stack stack;
    initStack(&stack);
    for (int i = 0; i < 3; ++i) {
        pushStack(&stack, i*100);
    }
    printStack(&stack);
    while (!isEmpty(&stack)) {
        printf("%d ", popStack(&stack));   //将栈中所有元素依次出栈
    }
}