c++51行贪吃蛇

#include <cstdio>
#include <deque>
#include <windows.h>
using namespace std;
COORD gSize{32, 16}, pos{1, 0}, food = gSize;
deque<COORD> snake(1, {0, 0});
int cdprintf(COORD cd, const char *s)
{
    return SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE), cd), printf(s);
}
int isLegal(COORD cd)
{
    for (deque<COORD>::iterator it = snake.begin(); it != snake.end(); ++it)
        if (it->X == cd.X && it->Y == cd.Y)
            return 0;
    return 0 <= cd.X && cd.X < gSize.X && 0 <= cd.Y && cd.Y < gSize.Y;
}
int main()
{
    for (int i = 0; i < gSize.Y; ++i)
        cdprintf({gSize.X, i}, "♂");
    cdprintf({0, gSize.Y}, "←↑↓→方向键移动，Space键暂停");
    for (int SCORE = 0, FOOD = 0, BACK = 0; isLegal({snake.front().X + pos.X, snake.front().Y + pos.Y}); Sleep(255))
    {
        if (BACK)
            --BACK;
        else
            cdprintf(snake.back(), " "), snake.pop_back();
        snake.push_front({snake.front().X + pos.X, snake.front().Y + pos.Y});
        cdprintf(snake.front(), "*");
        if (!isLegal(food))
        {
            char s[63];
            sprintf(s, "WuK的贪吃蛇 %d分", SCORE += FOOD), SetConsoleTitle(s);
            for (BACK += FOOD; !isLegal(food = {rand() % gSize.X, rand() % gSize.Y});)
                ;
            sprintf(s, "%d", FOOD = rand() % 3 + 1), cdprintf(food, s);
        }
        if (GetAsyncKeyState(VK_SPACE))
            MessageBox(NULL, "游戏很好玩？n请联系[email protected]", "By WuK", NULL);
        else if (GetAsyncKeyState(VK_UP) && pos.Y != 1)
            pos = {0, -1};
        else if (GetAsyncKeyState(VK_DOWN) && pos.Y != -1)
            pos = {0, 1};
        else if (GetAsyncKeyState(VK_LEFT) && pos.X != 1)
            pos = {-1, 0};
        else if (GetAsyncKeyState(VK_RIGHT) && pos.X != -1)
            pos = {1, 0};
    }
    MessageBox(NULL, "Game Over", "By WuK", NULL);
}