手写栈，求大佬帮忙看一下OrzOrz

#include<bits/stdc++.h>
#define int unsigned long long
using namespace std;

struct mystack{
	int Stack[5000005];
	int len;
	void push(int a){
		Stack[++len] = a;
	}
	int top(){
		return ((len == 0) ? -1 : Stack[len]);
	}
	bool pop(){
		Stack[len] = 0;
		if(len == 0)return false;
		len--;
		return true;
	}
	int empty(){
		return len;
	}
	void memset_stack(){
		for(int i = 0  ; i <= len ; i++)Stack[i] = 0;
	}
}Handwriting_stacks;

int n,t;

signed main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
	cin >> t;
	while(t--){
		cin >> n;
		string s = "";
		for(int i = 1 ; i <= n ; i++){
			cin >> s;
			if(s == "push"){
				int x;
				cin >> x;
				Handwriting_stacks.push(x);
			}else if(s == "pop"){
				if(Handwriting_stacks.pop() == false){
					cout << "Empty\n";
				}
			}else if(s == "query"){
				if(Handwriting_stacks.top() == -1){
					cout << "Anguei!\n";
				}else{
					cout << Handwriting_stacks.top() << '\n';
				}
			}else if(s == "size"){
				cout << Handwriting_stacks.empty() << '\n';
			}
		}
		Handwriting_stacks.memset_stack();
	}
	return 0;
}