8queen2.cpp

最早由德国数学家高斯提出八王后问题

// 8Queen2.cpp : Defines the enTRY point for the console application.
//

#include "stdafx.h"
//#include "graphics.h"
#include <stdlib.h>
#include <stdio.h>
#include <dos.h>
char n[3]={'0','0'};/*用于记录第几组解*/
int a[8],b[15],c[24],i;
int h[8]={127,177,227,277,327,377,427,477};/*每个皇后的行坐标*/
int l[8]={252,217,182,147,112,77,42,7};/*每个皇后的列坐标*/
void *arrow;

void TRY(int i);

int main(int argc, char* argv[])
{
	int gdrive=DETECT,gmode,errorcode;
	unsigned int size;
	initgraph(&gdrive,&gmode,"");
	errorcode=graphresult();

	if (errorcode!=grOk)
	{
		printf("Graphics error\n");exit(1);
	}

	rectangle(50,5,100,40);
	rectangle(60,25,90,33);
	/*画皇冠*/
	line(60,28,90,28);line(60,25,55,15);
	line(55,15,68,25);line(68,25,68,10);
	line(68,10,75,25);line(75,25,82,10);
	line(82,10,82,25);line(82,25,95,15);
	line(95,15,90,25);

	size=imagesize(52,7,98,38); arrow=malloc(size);
	getimage(52,7,98,38,arrow);/*把皇冠保存到缓冲区*/
	clearviewport();
	settextstyle(TRIPLEX_FONT, HORIZ_DIR, 4);
	setusercharsize(3, 1, 1, 1);
	setfillstyle(1,4);

	for (i=0;i<=7;i++) a[i]=1;
	for (i=0;i<=14;i++) b[i]=1;
	for (i=0;i<=23;i++) c[i]=1;
	for (i=0;i<=8;i++) line(125,i*35+5,525,i*35+5);/*画棋盘*/
	for (i=0;i<=8;i++) line(125+i*50,5,125+i*50,285);
	TRY(1);/*调用递归函数*/
	delay(3000);
	closegraph();
	free(arrow);

	return 0;
}


void TRY(int i)
{
	int j;
	for (j=1;j<=8;j++)
		if (a[j-1]+b[i+j-2]+c[i-j+7]==3) /*如果第i列第j行为空*/
		{a[j-1]=0;b[i+j-2]=0;c[i-j+7]=0;/*占用第i列第j行*/
		putimage(h[i-1],l[j-1],arrow,COPY_PUT);/*显示皇后图形*/
		delay(500);/*延时*/
		if(i<8) TRY(i+1);
		else /*输出一组解*/
		{
			n[1]++;if (n[1]>'9') {n[0]++;n[1]='0';
			}
			bar(260,300,390,340);/*显示第n组解*/
			outtextxy(275,300,n);
			delay(3000);
		}
		a[j-1]=1;b[i+j-2]=1;c[i-j+7]=1;
		putimage(h[i-1],l[j-1],arrow,XOR_PUT);/*消去皇后，继续寻找下一组解*/
		delay(500);
		}
}