南昌航空大学 软件学院 pta Java 第五次作业 蔡珂 opp
opp系列最难的一次作业来了
国庆玩high了，导致最后几天突击也只写了一题
甚至没写完QAQ
题目列表
7-1 点线形系列5-凸五边形的计算-1
用户输入一组选项和数据，进行与五边形有关的计算。
以下五边形顶点的坐标要求按顺序依次输入，连续输入的两个顶点是相邻顶点，第一个和最后一个输入的顶点相邻。
选项包括：
1：输入五个点坐标，判断是否是五边形，判断结果输出true/false。
2：输入五个点坐标，判断是凹五边形（false）还是凸五边形(true)，如果是凸五边形，则再输出五边形周长、面积，结果之间以一个英文空格符分隔。 若五个点坐标无法构成五边形，输出"not a pentagon"
3：输入七个点坐标，前两个点构成一条直线，后五个点构成一个凸五边形、凸四边形或凸三角形，输出直线与五边形、四边形或三角形相交的交点数量。如果交点有两个，再按面积从小到大输出被直线分割成两部分的面积（不换行）。若直线与多边形形的一条边线重合，输出"The line is coincide with one of the lines"。若后五个点不符合五边形输入，若前两点重合，输出"points coincide"。
以上3选项中，若输入的点无法构成多边形，则输出"not a polygon"。输入的五个点坐标可能存在冗余，假设多边形一条边上两个端点分别是x、y，边线中间有一点z，另一顶点s：
1）符合要求的输入：顶点重复或者z与xy都相邻，如：x x y s、x z y s、x y x s、s x y y。此时去除冗余点，保留一个x、一个y。
2) 不符合要求的输入：z不与xy都相邻，如：z x y s、x z s y、x s z y
输入格式:
基本格式：选项+":"+坐标x+","+坐标y+" "+坐标x+","+坐标y。点的x、y坐标之间以英文","分隔，点与点之间以一个英文空格分隔。
输出格式:
基本输出格式见每种选项的描述。
异常情况输出：
如果不符合基本格式，输出"Wrong Format"。
如果符合基本格式，但输入点的数量不符合要求，输出"wrong number of points"。
注意：输出的数据若小数点后超过3位，只保留小数点后3位，多余部分采用四舍五入规则进到最低位。小数点后
代码如下
import java.util.Scanner; // 需要导入 util 包
public class Main {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
// String ch = input.nextLine();
PointTaking a = new PointTaking();
a.ch = input.nextLine();//读入
double ans =a.Solve();
if (ans == -1)
System.out.printf("Wrong Format\n");
else if (ans == -2)
System.out.printf("wrong number of points\n");
else if (ans == -3)
System.out.printf("data error\n");
else if (ans==-4)
System.out.printf("not a pentagon\n");
else if (ans==-5)
System.out.printf("not a polygon");
else if (ans == 1)
System.out.printf("true\n");
else if (ans == 2)
System.out.printf("false\n");
else if(ans==4)
System.out.printf("points coincide\n");
}
}
class Line {
Point a ,b;
public Line(){
}
public Line(Point point1,Point point2){
a = new Point(point1);
b = new Point(point2);
}
public Line(Line line){
a = new Point();
b = new Point();
a.x = line.a.x;a.y = line.a.y;
b.x=line.b.x;b.y = line.b.y;
}
boolean judgeIntersection(Line line2){
if(slope()==line2.slope())
return false;
Point point = intersection(line2);
//System.out.printf("\n\n"+point.x+" "+point.y+"\n\n");
if(dotLineJudgment(point)&&line2.dotLineJudgment(point))
return true;
return false;
}
double slope(){//斜率
if(this.a.x==this.b.x)
return 9521462;
//System.out.printf("\n1511565sada\n");
return (this.a.y-this.b.y)/(this.a.x-this.b.x);
}
double intercept() {//截距
if(slope()==9521462)
return this.a.x;
if(slope()==0)
return 0;
return a.x-(this.slope())*a.y;
}
double pointVerticalDistanc(Point c){//点到线距离
if(this.a.x==this.b.x)
return Math.abs(c.x-this.a.x);
return (Math.abs((this.a.y-this.b.y)*c.x+(this.b.x-this.a.x)*c.y+this.a.x*this.b.y-this.a.y*this.b.x)/
(Math.sqrt((this.a.y-this.b.y)*(this.a.y-this.b.y)+(this.a.x-this.b.x)*(this.a.x-this.b.x))));
}
boolean sameIntersection(Line line1,Line line2){//判断相交点是否相同
Point point1=this.intersection(line1),point2=this.intersection(line2);
return point2.x == point1.x && point1.y == point2.y&&this.dotLineJudgment(point1)&&dotLineJudgment(point2)&&
line1.dotLineJudgment(point1)&&line2.dotLineJudgment(point2);
}
double dis(){
return a.DistanceCalculation(b);
}//线长
boolean judgeParallelism(Line line) {
return Math.abs((line.a.x-line.b.x )*(a.y-b.y)- (a.x-b.x )*(line.a.y-line.b.y))<0.05;
}
Point intersection(Line line){//求相交点
Point point1 = new Point();
point1.x=((line.a.x-line.b.x)*(this.a.y*this.b.x-this.a.x*this.b.y)-(this.a.x-this.b.x)*(line.a.y*line.b.x-line.a.x*line.b.y))/
((this.b.y-this.a.y)*(line.b.x-line.a.x)-(this.b.x-this.a.x)*(line.b.y-line.a.y));
point1.y=((line.a.y-line.b.y)*(this.a.y*this.b.x-this.a.x*this.b.y)-(this.a.y-this.b.y)*(line.a.y*line.b.x-line.a.x*line.b.y))/
((this.b.y-this.a.y)*(line.b.x-line.a.x)-(this.b.x-this.a.x)*(line.b.y-line.a.y));
return point1;
}
boolean dotLineJudgment(Point point){//判断点是否在直线上
Line line2 = new Line(a,point);
if(a.x==b.x)
return this.judgeParallelism(line2) &&Math.max(a.y,b.y)>=point.y&&Math.min(a.y,b.y)<=point.y;
else {
return this.judgeParallelism(line2) &&Math.max(a.x,b.x)>=point.x&&Math.min(a.x,b.x)<=point.x;
}
}
boolean vertical(Line line){
return (a.x - b.x) * (line.a.x - line.b.x) + (a.y - b.y) * (line.a.y - line.b.y) == 0;
}
boolean overlap(Line line){
if(a.x==b.x)
return (line.slope()==slope()&&line.intercept()==intercept())&&((line.a.y<=Math.max(a.y,b.y)&&line.a.y>=Math.min(a.y,b.y))||
(line.b.y<=Math.max(a.y,b.y)&&line.b.y>=Math.min(a.y,b.y)));
return (line.slope()==slope()&&line.intercept()==intercept())&&((line.a.x<=Math.max(a.x,b.x)&&line.a.x>=Math.min(a.x,b.x))||
(line.b.x<=Math.max(a.x,b.x)&&line.b.x>=Math.min(a.x,b.x)));
}
}
class Pentagon {
Line[] line = new Line [6];
public Pentagon(){}
public Pentagon(Point point1,Point point2,Point point3,Point point4,Point point5) {
for(int i=1;i<=5;i++){
line[i] = new Line();
line[i].a = new Point();
line[i].b = new Point();
}
line[1].a.x = point1.x;line[1].a.y = point1.y;
line[1].b.x = point2.x;line[1].b.y = point2.y;
line[2].a.x = point2.x;line[2].a.y = point2.y;
line[2].b.x = point3.x;line[2].b.y = point3.y;
line[3].a.x = point3.x;line[3].a.y = point3.y;
line[3].b.x = point4.x;line[3].b.y = point4.y;
line[4].a.x = point4.x;line[4].a.y = point4.y;
line[4].b.x = point5.x;line[4].b.y = point5.y;
line[5].a.x = point5.x;line[5].a.y = point5.y;
line[5].b.x = point1.x;line[5].b.y = point1.y;
}
boolean legal(){
for(int i=1;i<=5;i++) {
// System.out.printf("%f %f\n",line[i].a.x,line[i].a.y);
if ((line[i].a.x-line[i].b.x )*(line[i%5+1].a.y-line[i%5+1].b.y)== (line[i%5+1].a.x-line[i%5+1].b.x )*(line[i].a.y-line[i].b.y))
return false;
}
for(int i=1;i<=5;i++){
for (int j=1;j<=5;j++){
if(j!=(i%5+1)&&j!=(i+3)%5+1&&i!=j) {
// System.out.printf("%f %f %f %f\n",line[i].a.x,line[i].a.y,line[j].a.x,line[j].a.y);
if (line[i].judgeIntersection(line[j]))
return false;
}
}
}
return true;
}
double area(){
Triangle []tri=new Triangle[5];
Line[] lines= new Line[4];
lines[1] = new Line(line[1].a,line[2].b);
lines[2] = new Line(line[1].a,line[3].b);
tri[1]= new Triangle(line[1],line[2],lines[1]);
tri[2]= new Triangle(lines[1],line[3],lines[2]);
tri[3]= new Triangle(lines[2],line[4],line[5]);
return tri[1].area()+tri[2].area()+tri[3].area();
}
boolean bump(){//判断凹凸，凹为true
Triangle []tri=new Triangle[5];
Line[] lines= new Line[4];
double num = 0,temp = 0;
lines[1] = new Line(line[1].a,line[2].b);
lines[2] = new Line(line[1].a,line[3].b);
tri[1]= new Triangle(line[1],line[2],lines[1]);
tri[2]= new Triangle(lines[1],line[3],lines[2]);
tri[3]= new Triangle(lines[2],line[4],line[5]);
num = tri[1].area()+tri[2].area()+tri[3].area();
for(int i = 2;i<=5;i++){
lines[1]=new Line(line[i].a,line[i%5+1].b);
lines[2]=new Line(line[i].a,line[(i+1)%5+1].b);
tri[1]= new Triangle(line[i],line[i%5+1],lines[1]);
tri[2]= new Triangle(lines[1],line[(i+1)%5+1],lines[2]);
tri[3]=new Triangle(lines[2],line[(i+2)%5+1],line[(i+3)%5+1]);
temp = tri[1].area()+tri[2].area()+tri[3].area();
if(Math.abs(temp-num)>0.005)
return true;
}
return false;
}
double perimeter(){
return line[1].dis()+line[2].dis()+line[3].dis()+line[4].dis()+line[5].dis();
}
void partition(Line line1){
Quadrilateral qua = new Quadrilateral();
System.out.printf("2 ");
double s = area(),s2=0;
boolean f= false;
Triangle tri = new Triangle();
A:for(int i= 1;i <=5;i++){
if((line1.judgeIntersection(line[i])&&line1.judgeIntersection(line[i%5+1])&&!line1.judgeIntersection(line[(i+1)%5+1])&&
line1.judgeIntersection(line[(i+2)%5+1])&&line1.judgeIntersection(line[(i+3)%5+1])&&
(line1.sameIntersection(line[i],line[i%5+1])&&line1.sameIntersection(line[(i+3)%5+1],line[(i+2)%5+1])))||
(line1.judgeIntersection(line[i])&&line1.judgeIntersection(line[i%5+1])&&!line1.judgeIntersection(line[(i+1)%5+1])
&&!line1.judgeIntersection(line[(i+2)%5+1]) &&line1.judgeIntersection(line[(i+3)%5+1])
&&(line1.sameIntersection(line[i],line[i%5+1])))||
(line1.judgeIntersection(line[i])&&!line1.judgeIntersection(line[i%5+1])&&!line1.judgeIntersection(line[(i+1)%5+1])
&&line1.judgeIntersection(line[(i+2)%5+1]) &&line1.judgeIntersection(line[(i+3)%5+1])
&&(line1.sameIntersection(line[(i+3)%5+1],line[(i+2)%5+1])))||
(line1.judgeIntersection(line[i])&&!line1.judgeIntersection(line[i%5+1])&&!line1.judgeIntersection(line[(i+1)%5+1])&&!line1.judgeIntersection(line[(i+2)%5+1])&&line1.judgeIntersection(line[(i+3)%5+1]))){
tri = new Triangle(line[i].a,line1.intersection(line[i]),line1.intersection(line[(i+3)%5+1]));
s2 = tri.area();
f = true;
break A;
}
}
B:for(int i=1;i<=5;i++){
if((!line1.judgeIntersection(line[i])&&line1.judgeIntersection(line[i%5+1])&&!line1.judgeIntersection(line[(i+1)%5+1])&&//1
!line1.judgeIntersection(line[(i+2)%5+1])&&line1.judgeIntersection(line[(i+3)%5+1]))||
(!line1.judgeIntersection(line[i])&&line1.judgeIntersection(line[i%5+1])&&line1.judgeIntersection(line[(i+1)%5+1])&&//5
!line1.judgeIntersection(line[(i+2)%5+1])&&line1.judgeIntersection(line[(i+3)%5+1])&&
line1.sameIntersection(line[(i+1)%5+1],line[i%5+1]))){
qua = new Quadrilateral(line[i].a,line[i].b,line1.intersection(line[i%5+1]),line1.intersection(line[(i+3)%5+1]));
s2 = qua.area();
break B;
}
}
System.out.printf(printDouble(Math.min(s2,s-s2))+" "+printDouble(Math.max(s2,s-s2)));
}
public static double printDouble(double num) {
String str = String.format("%.3f",num);
num = Double.parseDouble(str);
return num;
}
}
class Quadrilateral {
Line []line = new Line[5];
public Quadrilateral(){}
public Quadrilateral(Point []points){
for(int i=1;i<=4;i++){
line[i]=new Line(points[i],points[i%4+1]);
}
}
public Quadrilateral(Point point1,Point point2,Point point3,Point point4){
line[1] = new Line(point1,point2);
line[2]= new Line(point2,point3);
line[3] = new Line(point3,point4);
line[4]= new Line(point4,point1);
}
boolean quadrilateralOrNot(){//非法三角形之大小大类型
return line[1].judgeIntersection(line[3])|| line[2].judgeIntersection(line[4]) || line[1].dotLineJudgment(line[3].a) || line[1].dotLineJudgment(line[3].b) || line[3].dotLineJudgment(line[1].a) || line[3].dotLineJudgment(line[1].b);
}
boolean parallel(){//判断平行四边形
return line[1].slope() == line[3].slope() && line[2].slope() == line[4].slope();
}
boolean judgeDiamond(){//判断是否菱形
return parallel()&&Math.abs(line[1].dis()-line[2].dis())<0.05;
}
boolean judgeRectangle(){//判断矩形
return line[1].vertical(line[2])&&line[1].judgeParallelism(line[3])&&line[2].judgeParallelism(line[4]);
}
boolean fourPointsCollinear(){//判断不能组成三角形或者四边形
// System.out.printf(line[1].slope()+" "+line[2].slope()+" "+line[3].slope()+" "+line[4].slope()+"\n");
return line[1].slope()==line[2].slope()&&line[2].slope()==line[3].slope()&&line[3].slope()==line[4].slope();
}
double perimeter(){//周长
return line[1].dis()+line[2].dis()+line[3].dis()+line[4].dis();
}
Triangle[] division(){//划分三角形
Line a = new Line(),b = new Line();
Triangle [] tri = new Triangle[5];
for(int i=1;i<=4;i++)
tri[i]= new Triangle();
a.a=line[1].a;a.b=line[3].a;
b.a=line[1].b;b.b=line[3].b;
tri[1].line[1]=line[1];
tri[1].line[2]=line[2];
tri[1].line[3]=a;
tri[2].line[1]=line[3];
tri[2].line[2]=line[4];
tri[2].line[3]=a;
tri[3].line[1]=line[1];
tri[3].line[2]=line[4];
tri[3].line[3]=b;
tri[4].line[1]=line[3];
tri[4].line[2]=line[2];
tri[4].line[3]=b;
return tri;
}
double area(){//面积
Triangle [] tri = division();
return Math.min(tri[1].area()+tri[2].area(),tri[3].area()+tri[4].area());
}
boolean bump(){//判断凹凸
Triangle [] tri = division();
return tri[1].area() + tri[2].area() == tri[3].area() + tri[4].area();
}
int focalPoints(Line line2) {//求线与其焦点数量
int num=0;
boolean []flag={false,false,false,false,false};
for(int i=1;i<=4;i++) {
if (line2.judgeIntersection(line[i]) ) {
num++;
flag[i] = true;
}
}
for(int i=1;i<=4;i++){
if(flag[i]&&line2.sameIntersection(line[i],line[i%4+1]))
num--;
}
return num;
}//4:-1,-1 1,1 0,0 2,0 3,0 0,5
//4:-1,-1 1,1 0,0 5,0 5,5 0,5
Triangle generateTriangle(){
Triangle tri =new Triangle();
if(line[1].slope()==line[2].slope())
tri=new Triangle(line[3],line[4],line[1].a,line[2].b);
else if(line[3].slope()==line[2].slope())
tri=new Triangle(line[4],line[1],line[2].a,line[3].b);
else if(line[3].slope()==line[4].slope())
tri=new Triangle(line[1],line[2],line[3].a,line[4].b);
else if(line[1].slope()==line[4].slope())
tri=new Triangle(line[2],line[3],line[4].a,line[1].b);
return tri;
}
Triangle returnTriangle(){
Triangle tri = new Triangle();
if(line[1].judgeParallelism(line[2])){
tri = new Triangle(line[3],line[4],line[1].a,line[2].b);
}
else if(line[2].judgeParallelism(line[3])){
tri = new Triangle(line[4],line[1],line[2].a,line[3].b);
}
else if(line[3].judgeParallelism(line[4])){
tri = new Triangle(line[1],line[2],line[3].a,line[4].b);
}
else if(line[4].judgeParallelism(line[1])){
tri = new Triangle(line[2],line[3],line[4].a,line[1].b);
}
return tri;
}
int parallelNum(){
int num = 0;
for(int i=1;i<=4;i++)
if(line[i].judgeParallelism(line[i%4+1])){
num++;
}
return num;
}
void pointRelation(Point point){
Triangle a=new Triangle(),b= new Triangle(),c= new Triangle(),d= new Triangle();
b= new Triangle(point,line[3].a,line[3].b);c= new Triangle(point,line[2].a,line[2].b);d= new Triangle(point,line[1].a,line[1].b);
a = new Triangle(point,line[4].a,line[4].b);
if(d.area()==0||b.area()==0||c.area()==0||a.area()==0)
System.out.println("on the quadrilateral");
else if(Math.abs(area()-a.area()-b.area()-c.area()-d.area())<0.0005)
System.out.printf("in the quadrilateral");
else
System.out.println("outof the quadrilateral");
}
// Quadrilateral[] division(Quadrilateral q,Line line2){
// return q;
// }
boolean illegalShape(){
for (int i=1;i<=4;i++)
if(line[i].slope()==line[i%4+1].slope()){
// System.out.printf(i+" "+(boolean)(line[i].a.x>line[i].b.x&&line[i%4+1].b.x>line[i%4+1].a.x)+" "+(boolean)(line[i].a.x<line[i].b.x&&line[i%4+1].b.x<line[i%4+1].a.x)+" "+(boolean)(line[i].a.y>line[i].b.y&&line[i%4+1].b.y>line[i%4+1].a.y)+" "+(boolean)(line[i].a.y<line[i].b.y&&line[i%4+1].b.y<line[i%4+1].a.y)+"\n");
if((line[i].a.x>line[i].b.x&&line[i%4+1].b.x>line[i%4+1].a.x)||
(line[i].a.x<line[i].b.x&&line[i%4+1].b.x<line[i%4+1].a.x)||
(line[i].a.y>line[i].b.y&&line[i%4+1].b.y>line[i%4+1].a.y)||
(line[i].a.y<line[i].b.y&&line[i%4+1].b.y<line[i%4+1].a.y))
return true;
}
return false;
}
boolean lineEdgeIntersection(Line line2){//线和线重叠
// System.out.printf("%f %f %f %f\n",line[1].slope(),line[2].slope(),line[3].slope(),line[4].slope());
return line2.overlap(line[1]) || line2.overlap(line[2]) ||
line2.overlap(line[3]) || line2.overlap(line[4]);
}
void partition(Line line1){
int num = 0;
Quadrilateral qua = new Quadrilateral();
System.out.printf("2 ");
double s = area(),s2=0;
Triangle tri = new Triangle();
if((line1.judgeIntersection(line[1])&&line1.judgeIntersection(line[2])&&line1.judgeIntersection(line[3])&&
line1.judgeIntersection(line[4])&&(line1.sameIntersection(line[1],line[2])&&line1.sameIntersection(line[3],line[4])))||
(line1.judgeIntersection(line[1])&&line1.judgeIntersection(line[2])&&!line1.judgeIntersection(line[3])
&&line1.judgeIntersection(line[4]) &&(line1.sameIntersection(line[1],line[2])))||
(line1.judgeIntersection(line[1])&&!line1.judgeIntersection(line[2])&&line1.judgeIntersection(line[3])
&&line1.judgeIntersection(line[4]) &&(line1.sameIntersection(line[3],line[4])))||
(line1.judgeIntersection(line[1])&&!line1.judgeIntersection(line[2])&&!line1.judgeIntersection(line[3])&&line1.judgeIntersection(line[4]))){
tri = new Triangle(line[1].a,line1.intersection(line[1]),line1.intersection(line[4]));
s2 = tri.area();
}
else if((line1.judgeIntersection(line[1])&&line1.judgeIntersection(line[2])&&line1.judgeIntersection(line[3])&&
line1.judgeIntersection(line[4])&&(line1.sameIntersection(line[2],line[3])&&line1.sameIntersection(line[1],line[4])))||
(line1.judgeIntersection(line[1])&&line1.judgeIntersection(line[2])&&line1.judgeIntersection(line[3])
&&!line1.judgeIntersection(line[4]) &&(line1.sameIntersection(line[3],line[2])))||
(line1.judgeIntersection(line[1])&&line1.judgeIntersection(line[2])&&!line1.judgeIntersection(line[3])
&&line1.judgeIntersection(line[4]) &&(line1.sameIntersection(line[1],line[4])))||
(line1.judgeIntersection(line[1])&&line1.judgeIntersection(line[2])&&!line1.judgeIntersection(line[3])&&!line1.judgeIntersection(line[4]))){
tri = new Triangle(line[2].a,line1.intersection(line[2]),line1.intersection(line[1]));
s2 = tri.area();
}
else if((!line1.judgeIntersection(line[1])&&line1.judgeIntersection(line[2])&&line1.judgeIntersection(line[3])
&&line1.judgeIntersection(line[4]) &&(line1.sameIntersection(line[3],line[4])))||
(line1.judgeIntersection(line[1])&&line1.judgeIntersection(line[2])&&line1.judgeIntersection(line[3])
&&!line1.judgeIntersection(line[4]) &&(line1.sameIntersection(line[1],line[2])))||
(!line1.judgeIntersection(line[1])&&line1.judgeIntersection(line[2])&&line1.judgeIntersection(line[3])&&!line1.judgeIntersection(line[4]))){
tri = new Triangle(line[3].a,line1.intersection(line[3]),line1.intersection(line[2]));
s2 = tri.area();
}
else if((line1.judgeIntersection(line[1])&&!line1.judgeIntersection(line[2])&&line1.judgeIntersection(line[3])
&&line1.judgeIntersection(line[4]) &&(line1.sameIntersection(line[1],line[4])))||
(!line1.judgeIntersection(line[1])&&line1.judgeIntersection(line[2])&&line1.judgeIntersection(line[3])
&&line1.judgeIntersection(line[4]) &&(line1.sameIntersection(line[2],line[3])))||
(!line1.judgeIntersection(line[1])&&!line1.judgeIntersection(line[2])&&line1.judgeIntersection(line[3])&&line1.judgeIntersection(line[4]))){
tri = new Triangle(line[4].a,line1.intersection(line[4]),line1.intersection(line[3]));
s2 = tri.area();
}
else if(line1.judgeIntersection(line[1])&&!line1.judgeIntersection(line[2])&&line1.judgeIntersection(line[3])&&
!line1.judgeIntersection(line[4])){
qua = new Quadrilateral(line[1].a,line1.intersection(line[1]),line1.intersection(line[3]),line[3].b);
s2 = qua.area();
}
else if(!line1.judgeIntersection(line[1])&&line1.judgeIntersection(line[2])&&!line1.judgeIntersection(line[3])&&
line1.judgeIntersection(line[4])){
qua = new Quadrilateral(line[2].a,line1.intersection(line[2]),line1.intersection(line[4]),line[4].b);
s2 = qua.area();
}
System.out.printf(printDouble(Math.min(s2,s-s2))+" "+printDouble(Math.max(s2,s-s2)));
}
public static double printDouble(double num) {
String str = String.format("%.3f",num);
num = Double.parseDouble(str);
return num;
}
}
class Triangle {
Line []line = new Line[8];
void printTri(){
System.out.printf("line[1] = %f %f %f %f \nline[2] = %f %f %f %f \nline[3] = %f %f %f %f\n",
line[1].a.x,line[1].a.y,line[1].b.x,line[1].b.y,
line[2].a.x,line[2].a.y,line[2].b.x,line[2].b.y,
line[3].a.x,line[3].a.y,line[3].b.x,line[3].b.y);
}
double area() {//三角形面积
double p= (Math.sqrt((line[1].a.x-line[1].b.x)*(line[1].a.x-line[1].b.x)+(line[1].a.y-line[1].b.y)*(line[1].a.y-line[1].b.y))+Math.sqrt((line[2].a.x-line[2].b.x)*(line[2].a.x-line[2].b.x)+(line[2].a.y-line[2].b.y)*(line[2].a.y-line[2].b.y))+ Math.sqrt((line[3].a.x-line[3].b.x)*(line[3].a.x-line[3].b.x)+(line[3].a.y-line[3].b.y)*(line[3].a.y-line[3].b.y)) )/2;
return Math.sqrt(p*(p- Math.sqrt((line[1].a.x-line[1].b.x)*(line[1].a.x-line[1].b.x)+(line[1].a.y-line[1].b.y)*(line[1].a.y-line[1].b.y)) )*(p - Math.sqrt((line[2].a.x-line[2].b.x)*(line[2].a.x-line[2].b.x)+(line[2].a.y-line[2].b.y)*(line[2].a.y-line[2].b.y)) )*(p- Math.sqrt((line[3].a.x-line[3].b.x)*(line[3].a.x-line[3].b.x)+(line[3].a.y-line[3].b.y)*(line[3].a.y-line[3].b.y)) ));
}
public Triangle(){
}
public Triangle(Line line1,Line line2,Point point1,Point point2){
line[1] = new Line(line1);
line[2] = new Line(line2);
line[3] = new Line(point1,point2);
}
public Triangle(Line line1,Line line2,Line line3){
line[1] = new Line(line1);
line[2] = new Line(line2);
line[3] = new Line(line3);
}
public Triangle(Point point1,Point point2,Point point3) {
for(int i=1;i<=3;i++){
line[i] = new Line();
line[i].a= new Point();
line[i].b = new Point();
}
line[1].a.x=point1.x;line[1].a.y=point1.y;
line[1].b.x=point2.x;line[1].b.y=point2.y;
line[2].a.x=point2.x;line[2].a.y=point2.y;
line[2].b.x=point3.x;line[2].b.y=point3.y;
line[3].a.x=point3.x;line[3].a.y=point3.y;
line[3].b.x=point1.x;line[3].b.y=point1.y;
}
boolean legal(){
for(int i=1;i<=3;i++) {
if ((line[i].a.x-line[i].b.x )*(line[i%3+1].a.y-line[i%3+1].b.y)== (line[i%3+1].a.x-line[i%3+1].b.x )*(line[i].a.y-line[i].b.y))
return false;
}
return true;
}
void pointRelation(Point point){//5:1,4 0,0 5,5 0,0 5,0
Triangle b= new Triangle(),c= new Triangle(),d= new Triangle();
// System.out.printf("%f %f %f %f %f %f\n",line[1].a.x,line[1].a.y,line[2].a.x,line[2].a.y,line[3].a.x,line[3].a.y);
b= new Triangle(point,line[3].a,line[3].b);c= new Triangle(point,line[2].a,line[2].b);d= new Triangle(point,line[1].a,line[1].b);
if(d.area()==0||b.area()==0||c.area()==0)
System.out.println("on the triangle");
else if(Math.abs(area()-b.area()-c.area()-d.area())<0.0005)
System.out.printf("in the triangle");
else
System.out.println("outof the triangle");
}
void division(Line line1){
int num = 0;
System.out.printf("2 ");
double s = area(),s2=0;
Triangle tri = new Triangle();
if((line1.judgeIntersection(line[1])&&line1.judgeIntersection(line[2])&&line1.judgeIntersection(line[3]
)&&(line1.sameIntersection(line[1],line[2])||line1.sameIntersection(line[2],line[3])))||
(line1.judgeIntersection(line[1])&&!line1.judgeIntersection(line[2])&&line1.judgeIntersection(line[3]))){
tri = new Triangle(line[1].a,line1.intersection(line[1]),line1.intersection(line[3]));
}
if((line1.judgeIntersection(line[1])&&line1.judgeIntersection(line[2])&&line1.judgeIntersection(line[3]
)&&(line1.sameIntersection(line[1],line[3])))||
(line1.judgeIntersection(line[1])&&line1.judgeIntersection(line[2])&&!line1.judgeIntersection(line[3]))){
tri = new Triangle(line[2].a,line1.intersection(line[2]),line1.intersection(line[1]));
}
if((line1.judgeIntersection(line[1])&&line1.judgeIntersection(line[2])&&line1.judgeIntersection(line[3]
))|| (!line1.judgeIntersection(line[1])&&line1.judgeIntersection(line[2])&&line1.judgeIntersection(line[3]))){
tri = new Triangle(line[1].a,line1.intersection(line[1]),line1.intersection(line[3]));
}s2 = tri.area();
System.out.printf(printDouble(Math.min(s2,s-s2))+" "+printDouble(Math.max(s2,s-s2)));
}
public static double areaCalculation(Point a,Point b,Point c,Line d,double s) {//计算面积case4
Line aa = new Line(a,b);
Line bb = new Line(a,c);
Point x1 = aa.intersection(d);
Point x2 = bb.intersection(d);
double q = (a.DistanceCalculation(b)*a.DistanceCalculation(c));
double p = (a.DistanceCalculation(x1)*a.DistanceCalculation(x2));
// System.out.printf(p+" "+q+" ");
// System.out.printf(s+" ");
return (s*p)/q;
}
public static double printDouble(double num) {
String str = String.format("%.3f",num);
num = Double.parseDouble(str);
return num;
}
}
class Point {//点的类
double x = 0 , y = 0 ;
public Point(){}
public Point(Point point){
x= point.x;
y= point.y;
}
double DistanceCalculation(Point b) {
return Math.sqrt((this.x-b.x)*(this.x-b.x)+(this.y-b.y)*(this.y-b.y));
}//返回两点距离
}
class PointTaking {
String ch;
int num2=0;
public static double printDouble(double num) {
String str = String.format("%.3f",num);
num = Double.parseDouble(str);
return num;
}
public static double vectorComputation(Point a,Point b,Point c){//计算点线是否相交
double x1 = a.x-c.x, y1=a.y-c.y,x2=b.x-c.x,y2=b.y-c.y;
return x1*y2-x2*y1;
}//  
boolean repetitionPointJudgment(Point a[],int x,int y){//相同点
for(int i=x;i<=y;i++)//如果一样则返回
for(int j = i+1;j<=y;j++)
if(a[i].x==a[j].x&&a[i].y==a[j].y)
return true;
return false;
}
public static double areaCalculation(Point a,Point b,Point c,Line d,double s) {//计算面积case4
Line aa = new Line(a,b);
Line bb = new Line(a,c);
Point x1 = aa.intersection(d);
Point x2 = bb.intersection(d);
double q = (a.DistanceCalculation(b)*a.DistanceCalculation(c));
double p = (a.DistanceCalculation(x1)*a.DistanceCalculation(x2));
// System.out.printf(p+" "+q+" ");
// Systemystem.out.printf(s+" ");
return (s*p)/q;
}
Point [] duplicate(Point[] points){
Point []point = new Point[10];Point []point2 = new Point[10];
Triangle tri = new Triangle();
boolean []flag = new boolean[]{false, false, false, false, false, false, false, false};
boolean []flag2 = new boolean[]{false, false, false, false, false, false, false, false};
num2 = 5;
for(int i=3;i<=7;i++) {
for(int j=i+1;j<=7;j++)
if(!flag[j]&&points[i].x==points[j].x&&points[i].y==points[j].y){
// System.out.printf(j+"\n");
flag[j]=true;
num2 -- ;
}
}
int pos=1;
for(int i=3;i<=7;i++)
if(!flag[i]){
point[pos++]= new Point(points[i]);
}
pos--;
for(int i=1;i<=pos;i++){
Line line1 = new Line(point[i],point[i%pos+1]);
Line line2 = new Line(point[i%pos+1],point[(i+1)%pos+1]);
if(line1.judgeParallelism(line2)) {
if(!flag2[i%pos+1])
{
// System.out.printf((i%pos+1)+"\n");
flag2[i%pos+1]=true;
num2--;
}
}
}
int pos2=1;
for(int i=1;i<=pos;i++)
if(!flag2[i]) {
point2[pos2++] = new Point(point[i]);
}
return point2;
}
double Solve() {
Point[] pointSet = new Point[15];//储存点
int pos = 0;
// String[]
String[] splitSet1 = this.ch.split(":");//将字符串以冒号分割，剥离选项与坐标
if (splitSet1.length != 2)
return -1;
if (!splitSet1[0].matches("[1-5]"))//判断选项是否合规
return -1;
int x = Integer.parseInt(splitSet1[0]);//剥离出第选项
int[] digitalDeposit = {0, 5, 5, 7 ,6, 5};//定义选项要的点数
for (int i = 1; i <= 10; i++)
pointSet[i] = new Point();//new多个点
String[] splitSet2 = splitSet1[1].split(" ");
for (String i : splitSet2) {//对分割的字符串遍历
int count=2;
String[] splitSet3 = i.split(",");
for (String j : splitSet3) {
if (!j.matches("^[+-]?(([1-9]\\d*\\.\\d+)|(0\\.\\d+)|([1-9]\\d*)|0)$"))//正则表达式判断是否合法
return -1;//返回输入错误
int pos2 = pos / 2 + 1;
// System.out.printf(pos2+"");
if ((pos & 1) == 0)//按位读入坐标
pointSet[pos2].x = Double.parseDouble(j);
else if ((pos & 1) == 1)
pointSet[pos2].y = Double.parseDouble(j);
pos++;
count--;
}
if(count!=0)
return -1;
}
if (splitSet2.length != digitalDeposit[x])
return -2;//返回错误点数量
return juSample(x,pointSet);
}
double juSample(int x, Point[] points){
if(x==1)
return sample1(points);
else if(x==2)
return sample2(points);
else if(x==3)
return sample3(points);
return -1;
}
double sample1(Point[] points){
Pentagon pentagon = new Pentagon(points[1],points[2],points[3],points[4],points[5]);
if(!pentagon.legal()||repetitionPointJudgment(points,1,5))
return 2;
return 1;
}
double sample2(Point[] points){
if(sample1(points)==2)
return -4;
Pentagon pentagon = new Pentagon(points[1],points[2],points[3],points[4],points[5]);
if(pentagon.bump())
return 2;
// System.out.printf(q.bump()+"\n");
System.out.printf("true "+printDouble(pentagon.perimeter())+" "+printDouble(pentagon.area()));
return 5;
}
double sample3(Point[] points){
if(points[1].x==points[2].x&&points[1].y == points[2].y)
return 4;
Line line = new Line(points[1],points[2]);
Triangle tri = new Triangle();
Quadrilateral qua = new Quadrilateral();
Point []point = duplicate(points);
if(num2==3) {
tri = new Triangle(point[1],point[2],point[3]);
tri.division(line);
}
else if(num2==4){
qua = new Quadrilateral(point);
qua.partition(line);
}
else{
Pentagon pent = new Pentagon(points[3],points[4],points[5],points[6],points[7]);
pent.partition(line);
}
return 5;
}
}
代码可以放心食用，什么？7-2？什么7-2
