C 语言经典100例题目：画图，综合例子2。（在TC中实现）。
程序分析：无。
程序源代码：
// Created by www.zhishitu.com on 15/11/9.// Copyright © 2015年 . All rights reserved.//#include "graphics.h"#define LEFT 0#define TOP 0#define RIGHT 639#define BOTTOM 479#define LINES 400#define MAXCOLOR 15int main(){ int driver,mode,error; int x1,y1; int x2,y2; int dx1,dy1,dx2,dy2,i=1; int count=0; int color=0; driver=VGA; mode=VGAHI; initgraph(&driver,&mode,""); x1=x2=y1=y2=10; dx1=dy1=2; dx2=dy2=3; while(!kbhit()) { line(x1,y1,x2,y2); x1+=dx1;y1+=dy1; x2+=dx2;y2+dy2; if(x1<=LEFT||x1>=RIGHT) dx1=-dx1; if(y1<=TOP||y1>=BOTTOM) dy1=-dy1; if(x2<=LEFT||x2>=RIGHT) dx2=-dx2; if(y2<=TOP||y2>=BOTTOM) dy2=-dy2; if(++count>LINES) { setcolor(color); color=(color>=MAXCOLOR)?0:++color; } } closegraph();}