[置頂]c++小さなゲームのヘビ食い

#include<stdio.h>
#include<stdlib.h>
#include<conio.h>
#include<windows.h>
#include<time.h>
#include<math.h>
#define sqr(x) x*x
int i,j,x,y,d,k,f,stx,sty,score,e,l,w,h;
char s[21][21];
int a[21][21];
int hard[13]={1,2,5,10,15,20,30,45,60,80,100};
void find()
{
	for(int q=1;q<=20;q++)
	    for(int r=1;r<=20;r++)
	        if(a[q][r]==e)
	        {
	        	s[q][r]=' ';
	        	return;
			}
}
int yd()
{
	if(w=='H'&&k=='P')return 0;
	if(w=='P'&&k=='H')return 0;
	if(w=='M'&&k=='K')return 0;
	if(w=='K'&&k=='M')return 0;
	if(w=='K')return 1;
	if(w=='P')return 1;
	if(w=='H')return 1;
	if(w=='M')return 1;
	return 0;
}
int main()
{
	for(i=1;i<=20;i++)
	    for(j=1;j<=20;j++)
	       s[i][j]=' ';
	s[9][10]=1;s[10][10]=1;s[11][10]=1;
	for(i=9;i<=11;i++)
	{
		a[i][10]=i-8;
	}
	stx=11;
	sty=10;
	e=1;
	srand(time(0));
	z:;
	x=rand()%20+1;
	y=rand()%20+1;
	while(s[x][y]!=' ')
	{
		x=rand()%20+1;
		y=rand()%20+1;
	}
	s[x][y]='*';
	l=3;
	for(i=1;i<=20;i++)
	{
		s[i][1]=2;
		s[1][i]=2;
		s[20][i]=2;
		s[i][20]=2;
	}
	w='P';
	h=12;
	while(!d)
	{
		system("cls");
		for(;kbhit();)w=getch();
		if(w!=0&&yd())k=w;
		if(k=='H')stx--;
		if(k=='M')sty++;
		if(k=='P')stx++;
		if(k=='K')sty--;
		if(s[stx][sty]=='*')
		{
			score++;
			while(s[x][y]!=' ')
			{
				x=rand()%20+1;
				y=rand()%20+1;
			}
			s[x][y]='*';
			l++;
			s[stx][sty]=1;
			a[stx][sty]=l;
		}
		else 
		if(s[stx][sty]!=' ')
		{
			for(i=1;i<=20;i++)
			{
			    for(j=1;j<=20;j++)
			        putchar(s[i][j]);
			    puts("");
			}
			printf("Game over!
score:%d
hard:%d",score,13-h);
			getch();
			getch();
			return 0;;
		}
		else
		{
			l++;
			s[stx][sty]=1;
			a[stx][sty]=l;
			find();
			e++;
		}
		for(i=1;i<=20;i++)
		{
		    for(j=1;j<=20;j++)
		        printf("%c",s[i][j]);
		    puts("");
		}
		printf("score:%d",score,13-h);
		printf("
hard:%d",13-h);
		if(score>=hard[13-h])h--;
		Sleep(h*sqr((int)sqrt(h))*3);
	}
	return 0;
}