.
{
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(); }
经典c程序100例==61--70
【程序61】
题目:打印出杨辉三角形(要求打印出10行如下图) 1.程序分析: 1
1 1
1 2 1 1 3 3 1
1 4 6 4 1
1 5 10 10 5 1 2.程序源代码: main() {int i,j;
int a[10][10]; printf(\
for(i=0;i<10;i++) {a[i][0]=1; a[i][i]=1;}
for(i=2;i<10;i++) for(j=1;j
a[i][j]=a[i-1][j-1]+a[i-1][j];
.
.
for(i=0;i<10;i++) {for(j=0;j<=i;j++) printf(\ printf(\ } }
============================================================== 【程序62】
题目:学习putpixel画点。
1.程序分析: 2.程序源代码:
#include \#include \main() {
int i,j,driver=VGA,mode=VGAHI; initgraph(&driver,&mode,\setbkcolor(YELLOW); for(i=50;i<=230;i+=20) for(j=50;j<=230;j++) putpixel(i,j,1);
for(j=50;j<=230;j+=20) for(i=50;i<=230;i++) putpixel(i,j,1); }
============================================================== 【程序63】
题目:画椭圆ellipse 1.程序分析: 2.程序源代码:
#include \#include \#include \main() {
int x=360,y=160,driver=VGA,mode=VGAHI; int num=20,i; int top,bottom;
initgraph(&driver,&mode,\top=y-30; bottom=y-30;
for(i=0;i ellipse(250,250,0,360,top,bottom); . . top-=5; bottom+=5; } getch(); } ============================================================== 【程序64】 题目:利用ellipse and rectangle 画图。 1.程序分析: 2.程序源代码: #include \#include \#include \main() { int driver=VGA,mode=VGAHI; int i,num=15,top=50; int left=20,right=50; initgraph(&driver,&mode,\for(i=0;i ellipse(250,250,0,360,right,left); ellipse(250,250,0,360,20,top); rectangle(20-2*i,20-2*i,10*(i+2),10*(i+2)); right+=5; left+=5; top+=10; } getch(); } ============================================================== 【程序65】 题目:一个最优美的图案。 1.程序分析: 2.程序源代码: #include \#include \#include \#include \#include \#include \#include \#define MAXPTS 15 #define PI 3.1415926 . . struct PTS { int x,y; }; double AspectRatio=0.85; void LineToDemo(void) { struct viewporttype vp; struct PTS points[MAXPTS]; int i, j, h, w, xcenter, ycenter; int radius, angle, step; double rads; printf(\getviewsettings( &vp ); h = vp.bottom - vp.top; w = vp.right - vp.left; xcenter = w / 2; /* Determine the center of circle */ ycenter = h / 2; radius = (h - 30) / (AspectRatio * 2); step = 360 / MAXPTS; /* Determine # of increments */ angle = 0; /* Begin at zero degrees */ for( i=0 ; i points[i].y = ycenter - (int)( sin(rads) * radius * AspectRatio ); angle += step; /* Move to next increment */ } circle( xcenter, ycenter, radius ); /* Draw bounding circle */ for( i=0 ; i {int driver,mode; driver=CGA;mode=CGAC0; initgraph(&driver,&mode,\setcolor(3); setbkcolor(GREEN); LineToDemo();} ============================================================== 【程序66】 题目:输入3个数a,b,c,按大小顺序输出。 1.程序分析:利用指针方法。 2.程序源代码: . . /*pointer*/ main() { int n1,n2,n3; int *pointer1,*pointer2,*pointer3; printf(\scanf(\pointer1=&n1; pointer2=&n2; pointer3=&n3; if(n1>n2) swap(pointer1,pointer2); if(n1>n3) swap(pointer1,pointer3); if(n2>n3) swap(pointer2,pointer3); printf(\} swap(p1,p2) int *p1,*p2; {int p; p=*p1;*p1=*p2;*p2=p; } ============================================================== 【程序67】 题目:输入数组,最大的与第一个元素交换,最小的与最后一个元素交换,输出数组。 1.程序分析:谭浩强的书中答案有问题。 2.程序源代码: main() { int number[10]; input(number); max_min(number); output(number); } input(number) int number[10]; {int i; for(i=0;i<9;i++) scanf(\ scanf(\} max_min(array) int array[10]; {int *max,*min,k,l; int *p,*arr_end; arr_end=array+10; .