绘制矩形

#include <graphics.h>
main()
{
    int gdriver, gmode;
    gdriver = DETECT;
    initgraph(&gdriver, &gmode, "");       /*图形方式初始化*/
    setcolor(RED);          /*设置作图颜色*/
    setlinestyle(DASHED_LINE, 0, 3);       /*设置线的宽度和形式*/
    rectangle(100, 100, 550, 350);        /*画矩形*/
    getch();
    closegraph();          /*退出图形状态*/
}