顺序栈的入栈出栈操作但是只能输入没有输出怎么办

Question

这是我的代码

#include <stdio.h>
#include <malloc.h>
#define sizemax 10
#define error 0
#define ok 1

typedef struct {
    int *base;
    int *top;

} sqstack;

int init(sqstack *s) {
    s = (sqstack *)malloc(sizeof(sqstack));
    s->base=NULL;
    s->top=NULL;
    return ok;
}


//入栈
int push(sqstack *s, int m) {
    if (s->top - s->base == sizemax)
        return error;
    *(s->top) = m;
    s->top++;
    return ok;
}
//出栈 
int pop(sqstack *s) {
    int n;

    if (s->top==NULL) {
        return error;
    }
    n = *(s->top);
    s->top--;
    return n;
}


int main() {
    sqstack s;
    init(&s);
    int a, e, i,j;
    for (i = 0; i < 5; i++) {
        scanf("%d", &e);
        push(&s, e);
    }
    printf("\n");
    printf("pop a number \n");
    scanf("%d", &a);
    for (j = 0; j < a; j++) {
        printf("%d ",pop(&s));
    }
    return 0;

}


































































































































#include <stdio.h>
#include <malloc.h>
#define sizemax 10
#define error 0
#define ok 1

typedef struct {
    int *base;
    int *top;

} sqstack;

int init(sqstack *s) {
    s = (sqstack *)malloc(sizeof(sqstack));
    s->base=NULL;
    s->top=NULL;
    return ok;
}


//入栈
int push(sqstack *s, int m) {
    if (s->top - s->base == sizemax)
        return error;
    *(s->top) = m;
    s->top++;
    return ok;
}
//出栈 
int pop(sqstack *s) {
    int n;

    if (s->top==NULL) {
        return error;
    }
    n = *(s->top);
    s->top--;
    return n;
}


int main() {
    sqstack s;
    init(&s);
    int a, e, i,j;
    for (i = 0; i < 5; i++) {
        scanf("%d", &e);
        push(&s, e);
    }
    printf("\n");
    printf("pop a number \n");
    scanf("%d", &a);
    for (j = 0; j < a; j++) {
        printf("%d ",pop(&s));
    }
    return 0;

}

Answer 1

#include <stdio.h>
#include <stdlib.h>
#define sizemax 10
#define error 0
#define ok 1
typedef struct {
    int *base;
    int *top;
} sqstack;
int init(sqstack *s) {
    s->top = s->base = (int *)malloc(sizemax*sizeof(int));
    return ok;
}
//入栈
int push(sqstack *s, int m) {
    if (s->top - s->base == sizemax)
        return error;
    *(s->top) = m;
    s->top++;
    return ok;
}
//出栈 
int pop(sqstack *s) {
    int n;
    if (s->top==s->base) {
        return error;
    }
    s->top--;
    n = *(s->top);
    return n;
}
int main() {
    sqstack s;
    init(&s);
    int a, e, i,j;
    for (i = 0; i < 5; i++) {
        scanf("%d", &e);
        push(&s, e);
    }
    printf("\n");
    printf("pop a number \n");
    scanf("%d", &a);
    for (j = 0; j < a; j++) {
        printf("%d ",pop(&s));
    }
    free(s.base);
    return 0;
}