补全代码#include<stdio.h> #include<stdlib.h> typedef struct Stack{ int *data; int size, top; }Stack; Stack *init_stack(int n) { Stack *s = (Stack *)malloc(sizeof(Stack)); s->data = (int *)malloc(sizeof(int)); s->top = -1; s->size = n; return s; } void clear(Stack *s) { free(s->data); free(s); } int main() { return 0; }

这是一个基本的栈结构的定义和初始化函数以及清空函数的代码，但是缺少了栈的一些操作函数，比如 push()、pop()、peek() 等。可以参考下面的代码进行补充：

#include <stdio.h>
#include <stdlib.h>

typedef struct Stack{
    int *data;
    int size, top;
}Stack;

Stack *init_stack(int n) {
    Stack *s = (Stack *)malloc(sizeof(Stack));
    s->data = (int *)malloc(sizeof(int) * n);
    s->top = -1;
    s->size = n;
    return s;
}

void clear(Stack *s) {
    free(s->data);
    free(s);
}

int push(Stack *s, int x) {
    if (s->top == s->size - 1) {
        return 0; // 栈满了
    }
    s->top++;
    s->data[s->top] = x;
    return 1;
}

int pop(Stack *s) {
    if (s->top == -1) {
        return 0; // 栈空了
    }
    s->top--;
    return 1;
}

int peek(Stack *s) {
    if (s->top == -1) {
        return -1; // 栈空了
    }
    return s->data[s->top];
}

int main() {
    Stack *s = init_stack(10);
    push(s, 1);
    push(s, 2);
    push(s, 3);
    printf("%d\n", peek(s)); // 输出3
    pop(s);
    printf("%d\n", peek(s)); // 输出2
    clear(s);
    return 0;
}