飞机大战怎么加边框限制

不知道怎么加边框也不知道加在哪😭
#include
#include<conio.h>
#include<time.h>
using namespace std;

int main()
{
int x = 5, y = 20;//飞机坐标
char input;//用于接收输入
bool isfire = false;//发射子弹的标志
int enemy_x = 6;//敌机坐标
bool iskilled = false;//敌机击中标志

srand(time(NULL));//随机函数种子重置
enemy_x = rand() % 20;//让敌机坐标随机产生

while (true)
{
    /***********在(x,y)处显示飞机,分别用for,while,do,,,while实现************/
    system("cls");
    //用|表示子弹,根据isfire标志判断飞机上方显示空格,还是子弹。
    //在飞机上方输出y-1行。
    if (!iskilled)
    {
        //显示敌机
        //敌机左边输出enemy_x-1个空格
        for (int i = 0; i < enemy_x - 1; i++)
        {
            cout << " ";
        }
        cout << " ▲" << endl;

    }
    if (isfire)//发射子弹,在飞机上方显示。
    {
        //在飞机上方输出y-1行。
        for (int i = 1; i < y; i++)
        {
            for (int j = 1; j < x; j++)//左边输出x-1个空格
            {
                cout << " ";
            }
            cout << "   ||" << endl;
        }
    }
    else//没发射子弹
    {
        //在飞机上方输出y-1行,
        int i = y - 1;
        while (i > 0)
        {
            cout << endl;
            i--;
        }
    }
    //在左边输出x-1个空格
    int i = x - 1;
    do
    {
        cout << " ";
        i--;

    } while (i > 0);
    //输出飞机

    cout << "   !!" << endl;
    //在左边输出x-1个空格
    i = x - 1;

    while (i > 0)
    {
        cout << " ";
        i--;
    }



    cout << " ▲▲▲" << endl;
    //在左边输出x-1个空格
    for (i = 1; i < x; i++)
    {
        cout << " ";

    }
    cout << "  ^  ^" << endl;

    //cin>>input;用cin接受输入的方向信息


    input = _getch();

    if (input == 'a' || input == 75)
    {
        x--;
        isfire = false;//将子弹标志消除

        if (iskilled)//若敌机被击中,产生新的敌机
        {
            iskilled = false;
            enemy_x = rand() % 20;


        }
    }
    if (input == 'd' || input == 77)
    {
        x++;
        isfire = false;//将子弹标志消除

        if (iskilled)
        {
            iskilled = false;
            enemy_x = rand() % 20;

        }
    }
    if (input == 's' || input == 80)
    {
        y++;
        isfire = false;//将子弹标志消除

        if (iskilled)
        {
            iskilled = false;
            enemy_x = rand() % 20;

        }
    }
    if (input == 'w' || input == 72)
    {
        y--;
        isfire = false;//将子弹标志消除
        if (iskilled)
        {
            iskilled = false;
            enemy_x = rand() % 20;
        }
    }
    if (input == ' ')
    {
        isfire = true;
        if (x = enemy_x)//子弹坐标和敌机坐标一致,表示击中
        {
            iskilled = true;
        }

    }

}