11.c.txt

画直线

#include"stdio.h"
#include"stdlib.h"
#include"graphics.h"
#include"math.h"
void myinitgraph()
{  int  GraphDriver;
   int  GraphMode;
   int  ErrorCode;
   GraphDriver=DETECT;
   initgraph(&GraphDriver,&GraphMode,"");
   ErrorCode=graphresult();
   if(ErrorCode!=grOk)
      {printf("Graphics System Init Error:%s",grapherrormsg(ErrorCode));
       exit(1);}
 }
void  Midcircle(int x0,int y0,int r,int color)
 {   int x, y, d=1-r;
    for(x=0,y=r;x<=y;x++)
      { putpixel((x+x0)+300,(y+y0)+250,color);
	putpixel((y+x0)+300,(x+y0)+250,color);
	putpixel((y+x0)+300,(-x+y0)+250,color);
	putpixel((x+x0)+300,(-y+y0)+250,color);
	putpixel((-x+x0)+300,(y+y0)+250,color);
	putpixel((-y+x0)+300,(x+y0)+250,color);
	putpixel((-y+x0)+300,(-x+y0)+250,color);
	putpixel((-x+x0)+300,(-y+y0)+250,color);
	if(d<=0) d+=2*x+3;
	else  { d+=2*(x-y)+5;   y--;}
      }
  }
main()
 {  int x0,y0,r,color;
    printf("Input x0,y0,r,color:");
    scanf("%d,%d,%d,%d",&x0,&y0,&r,&color);
    myinitgraph();
    Midcircle(x0,y0,r,color);
 }