目录
- #include "graphics.h"
- #include<conio.h>
- int main()
- {
- int i;
- float j = 1, k = 1;
- initgraph(640, 480);
- setbkcolor(YELLOW);
- cleardevice();
- for (i = 0;i <= 25;i++)
- {
- setlinestyle(PS_SOLID, 4);
- setlinecolor(BLUE);
- circle(310, 250, k);
- k = k + j;
- j = j + 0.3;
- }
- _getch();
- closegraph();//关闭窗口
- }

- #include "graphics.h"
- #include<conio.h>
- int main()
- {
- int i;
- float x0, y0, y1, x1;
- float j = 12, k;
- initgraph(640, 480);
- setbkcolor(GREEN);
- cleardevice();
- x0 = 263;y0 = 263;y1 = 275;x1 = 275;
- for (i = 0;i <= 18;i++)
- {
- setlinestyle(PS_SOLID, 4);
- setlinecolor(BLUE);
- line(x0, y0, x0, y1);
- x0 = x0 - 5;
- y0 = y0 - 5;
- x1 = x1 + 5;
- y1 = y1 + 5;
- j = j + 10;
- }
- x0 = 263;y1 = 275;y0 = 263;
- for (i = 0;i <= 20;i++)
- {
- setlinestyle(PS_SOLID, 4);
- setlinecolor(BLUE);
- line(x0, y0, x0, y1);
- x0 = x0 + 5;
- y0 = y0 + 5;
- y1 = y1 - 5;
- }
- _getch();
- closegraph();//关闭窗口
- }

程序分析:利用for循环控制100 - 999个数,每个数分解出个位,十位,百位。
- #include <graphics.h>
- #include<conio.h>
- int main()
- {
- int x0, y0, y1, x1, i;
- initgraph(640, 480);
- setbkcolor(YELLOW);
- cleardevice();
- x0 = 263;y0 = 263;y1 = 275;x1 = 275;
- for (i = 0;i <= 18;i++)
- {
- setlinestyle(PS_SOLID, 4);
- setlinecolor(BLUE);
- rectangle(x0, y0, x1, y1);
- x0 = x0 - 5;
- y0 = y0 - 5;
- x1 = x1 + 5;
- y1 = y1 + 5;
- }
- setcolor(2);
- circle(269, 269, 137);
- _getch();
- closegraph();//关闭窗口
- }

- # define PAI 3.1415926
- # define B 0.809
- # include "graphics.h"
- #include "math.h"
- #include<conio.h>
- int main()
- {
- int i, j, k, x0, y0, x, y;
- float a;
- initgraph(640, 480);
- setlinestyle(PS_SOLID, 3);
- setlinecolor(BLUE);
- setbkcolor(GREEN);
- cleardevice();
- x0 = 150;y0 = 100;
- circle(x0, y0, 10);
- circle(x0, y0, 20);
- circle(x0, y0, 50);
- for (i = 0;i < 16;i++)
- {
- a = (2 * PAI / 16) * i;
- x = ceil(x0 + 48 * cos(a));
- y = ceil(y0 + 48 * sin(a) * B);
- setlinestyle(PS_SOLID, 3);
- setlinecolor(BLUE);
- line(x0, y0, x, y);
- }
- setcolor(3);circle(x0, y0, 60);
- /* Make 0 time normal size letters */
- _getch();
- setfillstyle(10, YELLOW);
- floodfill(202, 100, WHITE);
- _getch();
- for (k = 0;k <= 500;k++)
- {
- setlinestyle(PS_SOLID, 4);
- setlinecolor(BLUE);
- for (i = 0;i <= 16;i++)
- {
- a = (2 * PAI / 16) * i + (2 * PAI / 180) * k;
- x = ceil(x0 + 48 * cos(a));
- y = ceil(y0 + 48 + sin(a) * B);
- setlinestyle(PS_SOLID, 3);
- setlinecolor(BLUE);
- line(x0, y0, x, y);
- }
- for (j = 1;j <= 50;j++)
- {
- a = (2 * PAI / 16) * i + (2 * PAI / 180) * k - 1;
- x = ceil(x0 + 48 * cos(a));
- y = ceil(y0 + 48 * sin(a) * B);
- line(x0, y0, x, y);
- }
- }
- restorecrtmode();
- _getch();
- closegraph();//关闭窗口
- }

- #include "graphics.h"
- #include<conio.h>
- #define LEFT 0
- #define TOP 0
- #define RIGHT 639
- #define BOTTOM 479
- #define LINES 400
- #define MAXCOLOR 15
- int main()
- {
- int error=0;
- int x1, y1;
- int x2, y2;
- int dx1, dy1, dx2, dy2, i = 1;
- int count = 0;
- int color = 0;
- initgraph(640, 480);
- 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)
- {
- setlinestyle(PS_SOLID, 0);
- setlinecolor(BLUE);
- color = (color >= MAXCOLOR) ? 0 : ++color;
- }
- }
- closegraph();
- _getch();
- closegraph();//关闭窗口
- }