南昌航空大学 软件学院 pta Java 第三次作业 蔡珂 opp

第三次作业好像是不太一样了hhhh
写正则表达式写到怀疑人生
但机智如我
难点和思路会放在阶段总结性的博客中
这里就贴贴代码
先看题

题目列表

目录

• 题目列表
  • 7-1 点线形系列1-计算两点之间的距离
  • 7-2 点线形系列2-线的计算
  • 7-3 点线形系列3-三角形的计算

7-1 点线形系列1-计算两点之间的距离

输入两个点的坐标，计算两点之间的距离

输入格式:

4个double类型的实数，两个点的x，y坐标，依次是x1、y1、x2、y2，两个点的坐标之间以空格分隔，每个点的x,y坐标以英文“,”分隔。例如：0,0 1,1或0.1,-0.3 +3.5,15.6。
若输入格式非法，输出"Wrong Format"。
若输入格式合法但坐标点的数量超过两个，输出“wrong number of points;

输出格式:

计算所得的两点之间的距离。例如：1.4142135623730951

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();//读入答案
        if(ans==-1)
            System.out.printf("Wrong Format\n");
        else if(ans==-2)
            System.out.printf("wrong number of points\n");
        else
            System.out.printf(ans+"\n");
    }
}

class Point {//点的类
    double x = 0 , y = 0 ;
    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;
    double Solve() {
        Point a = new Point();
        int pos = 0;
        Point b = new Point();
        //  String[]
        String[] c  = this.ch.split(" ");//将字符串以空格分割

        for(String i:c) {//对分割的字符串遍历
            String[] d = i.split(",");
            for(String j:d) {
                //  System.out.printf(j+"\n");
                if(!j.matches("^[+-]?(([0-9][1-9]*\\.\\d+)|(0\\.\\d+)|([0-9][1-9]*))$"))//正则表达式判断是否合法
                    return -1;//返回输入错误
                if(pos==0)//按位读入坐标x1,y1,x2,y2
                    a.x =Double.parseDouble(j);
                else if(pos == 1)
                    a.y = Double.parseDouble(j);
                else if(pos == 2)
                    b.x=Double.parseDouble(j);
                else
                    b.y =Double.parseDouble(j);
                pos++;
            }

        }
        if(c.length!=2)
            return  -2;//返回错误点数量
        return a.DistanceCalculation(b);
    }

}

7-2 点线形系列2-线的计算

用户输入一组选项和数据，进行与直线有关的计算。选项包括：
1：输入两点坐标，计算斜率，若线条垂直于X轴，输出"Slope does not exist"。
2：输入三个点坐标，输出第一个点与另外两点连线的垂直距离。
3：输入三个点坐标，判断三个点是否在一条线上，输出true或者false。
4：输入四个点坐标，判断前两个点所构成的直线与后两点构成的直线是否平行，输出true或者false.
5：输入四个点坐标，计算输出前两个点所构成的直线与后两点构成的直线的交点坐标，x、y坐标之间以英文分隔","，并输出交叉点是否在两条线段之内（不含四个端点）的判断结果(true/false)，判断结果与坐标之间以一个英文空格分隔。若两条线平行，没有交叉点，则输出"is parallel lines,have no intersection point"。

输入格式:

基本格式：选项+":"+坐标x+","+坐标y+" "+坐标x+","+坐标y。
例如：1:0,0 1,1
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"。
不论哪个选项，如果格式、点数量都符合要求，但构成任一条线的两个点坐标重合，输出"points coincide"，

输出格式:

见题目描述。

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();//读入答案
        if(ans==-1)
            System.out.printf("Wrong Format\n");
        else if(ans==-2)
            System.out.printf("wrong number of points\n");
        else if(ans==1)
            System.out.printf("true\n");
        else if(ans==2)
            System.out.printf("false\n");
    }
}

class Line {
    Point a ,b;
    double slope(){//斜率
        if(this.a.x==this.b.x)
            return 0;
        return (this.a.y-this.b.y)/(this.a.x-this.b.x);
    }
    double intercept() {//截距
            return this.a.x-(this.slope())*this.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);
        if(this.a.y==this.b.y)
            return Math.abs(c.y-this.a.y);
        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));
    }
    Point intersection(Line line){
        double t1,t2;
        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;
    }
}
class Point {//点的类
    double x = 0 , y = 0 ;
    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;
    double Solve() {
        Point[] pointSet = new Point[15];
        int pos = 0;
        //  String[]
        String[] splitSet2;
        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= {0,2,3,3,4,4};//定义选项要的点数
        for(int i=1;i<=10;i++)
            pointSet[i] = new Point();//new多个点
        splitSet2 = splitSet1[1].split(" ");
        for(String i:splitSet2) {//对分割的字符串遍历
            String[] splitSet3 = i.split(",");
            int count=2;
            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
        for(int i=1;i<=digitalDeposit[x];i++){//如果一样则返回
          // System.out.printf("%f %f\n",pointSet[i].x,pointSet[i].y);
            for(int j = i+1;j<=digitalDeposit[x];j++)
                if(pointSet[i].x==pointSet[j].x&&pointSet[i].y==pointSet[j].y) {
                    System.out.printf("points coincide\n");
                    return 4;
                }
            }
        Line line = new Line();
        if(x==1) {//1
            if(pointSet[1].x==pointSet[2].x) {
                System.out.printf("Slope does not exist");
                return 4;
            }

            line.a=pointSet[1];
            line.b=pointSet[2];
            System.out.printf(line.slope()+"");
        }
        else if(x==2) {
            line.a = pointSet[2];
            line.b = pointSet[3];
            System.out.printf(line.pointVerticalDistanc(pointSet[1])+"");
            return 4;
        }
        else if(x==3){
            Line line2= new Line();
            line2.a = line.a = pointSet[1];
            line.b=pointSet[2];
            line2.b = pointSet[3];
            if(line2.slope()==line.slope())
                return 1;
            return 2;
        }
        else if(x==4){
            Line line2= new Line();
            line.a = pointSet[1];
            line.b = pointSet[2];
            line2.a = pointSet[3];
            line2.b = pointSet[4];
            if((line.a.x-line.b.x)*(line2.a.y-line2.b.y)!=(line2.a.x-line2.b.x)*(line.a.y-line.b.y))
                return 2;
            return 1;
        }
        else if(x==5){
            Line line2= new Line();
            line.a = pointSet[1];
            line.b = pointSet[2];
            line2.a = pointSet[3];
            line2.b = pointSet[4];
            if(line2.slope()==line.slope()){
                System.out.print("is parallel lines,have no intersection point");

                return 4;
            }
            Point point= line.intersection(line2);
            // System.out.printf("111");
            System.out.printf(point.x+","+point.y+" ");
            if((point.x<Math.max(line.a.x,line.b.x)&&point.x>Math.min(line.a.x,line.b.x))||(point.x<Math.max(line2.a.x,line2.b.x)&&point.x>Math.min(line2.a.x,line2.b.x)))
                System.out.printf("true");
            else
                System.out.printf("false");
        }
        return 5;
    }

}

7-3 点线形系列3-三角形的计算

用户输入一组选项和数据，进行与三角形有关的计算。选项包括：
1：输入三个点坐标，判断是否是等腰三角形、等边三角形，判断结果输出true/false，两个结果之间以一个英文空格符分隔。
2：输入三个点坐标，输出周长、面积、重心坐标，三个参数之间以一个英文空格分隔，坐标之间以英文","分隔。
3：输入三个点坐标，输出是钝角、直角还是锐角三角形，依次输出三个判断结果（true/false），以一个英文空格分隔，
4：输入五个点坐标，输出前两个点所在的直线与三个点所构成的三角形相交的交点数量，如果交点有两个，则按面积大小依次输出三角形被直线分割成两部分的面积。若直线与三角形一条线重合，输出"The point is on the edge of the triangle"
5：输入四个点坐标，输出第一个是否在后三个点所构成的三角形的内部（输出in the triangle/outof triangle）。
必须使用射线法，原理：由第一个点往任一方向做一射线，射线与三角形的边的交点（不含点本身）数量如果为1，则在三角形内部。如果交点有两个或0个，则在三角形之外。若点在三角形的某条边上，输出"on the triangle"

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"。
如果输入的三个点无法构成三角形，输出"data error"。
注意：输出的数据若小数点后超过6位，只保留小数点后6位，多余部分采用四舍五入规则进到最低位。小数点后若不足6位，按原始位数显示，不必补齐。例如：1/3的结果按格式输出为 0.333333，1.0按格式输出为1.0

选项4中所输入线的两个点坐标重合，输出"points coincide"，

代码如下

import java.util.Scanner; // 需要导入 util 包
import java.util.Arrays;
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();//读入答案
        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==1)
            System.out.printf("true\n");
        else if(ans==2)
            System.out.printf("false\n");

    }
}


class Line {
    Point a ,b;
    double slope(){//斜率
        if(this.a.x==this.b.x)
            return 0;
        return (this.a.y-this.b.y)/(this.a.x-this.b.x);
    }
    double intercept() {//截距
            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))));
    }
    int judgeIntersection(Line line){
        if(slope()==line.slope()&&intercept()==line.slope())
            return 0;
        if(this.slope()==line.slope())
            return -1;
        Point point = this.intersection(line);
        if(point.x<=Math.max(line.a.x,line.b.x)&&point.x>=Math.min(line.a.x,line.b.x)&&point.y<=Math.max(line.a.y,line.b.y)&&point.y>=Math.min(line.a.y,line.b.y))
            return 1;

        return -1;
    }
    boolean sameIntersection(Line line1,Line line2){//判断相交点是否相同
        Point point1=this.intersection(line1),point2=this.intersection(line2);
        if(point2.x==point1.x&&point1.y==point2.y)
            return true;
        return false;
    }
    double dis(){
        return a.DistanceCalculation(b);
    }

    boolean judgeParallelism(Line a) {
        if(a.slope()==this.slope()) return true;
        return  false;
    }
    Point intersection(Line line){//求相交点
        double t1,t2;
        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;
    }
}


class Point {//点的类
    double x = 0 , y = 0 ;
    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 Triangle {
    Line a,b,c;
    double area() {
        double p= (Math.sqrt((a.a.x-a.b.x)*(a.a.x-a.b.x)+(a.a.y-a.b.y)*(a.a.y-a.b.y))+Math.sqrt((b.a.x-b.b.x)*(b.a.x-b.b.x)+(b.a.y-b.b.y)*(b.a.y-b.b.y))+ Math.sqrt((c.a.x-c.b.x)*(c.a.x-c.b.x)+(c.a.y-c.b.y)*(c.a.y-c.b.y)) )/2;
        return Math.sqrt(p*(p- Math.sqrt((a.a.x-a.b.x)*(a.a.x-a.b.x)+(a.a.y-a.b.y)*(a.a.y-a.b.y)) )*(p - Math.sqrt((b.a.x-b.b.x)*(b.a.x-b.b.x)+(b.a.y-b.b.y)*(b.a.y-b.b.y)) )*(p- Math.sqrt((c.a.x-c.b.x)*(c.a.x-c.b.x)+(c.a.y-c.b.y)*(c.a.y-c.b.y)) ));
    }

}

class PointTaking {
    String ch;

    public static double printDouble(double num) {
        String str = String.format("%.6f",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;
    }
    public  static  double areaCalculation(Point a,Point b,Point c,Line d,double s) {//计算面积case4
        Line aa = new Line();
        Line bb = new Line();
        aa.a=a;aa.b=b;
        bb.a=a;bb.b=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;
    }

    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, 3, 3, 3, 5, 4};//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

        Line line = new Line();
        if (x == 1) {//1
            int num = 0;
            double[] distance = new double [5];
            distance[1]=pointSet[1].DistanceCalculation(pointSet[2]);
            distance[2]=pointSet[1].DistanceCalculation(pointSet[3]);
            distance[3]=pointSet[2].DistanceCalculation(pointSet[3]);
            Arrays.sort(distance,0,4);
            //  System.out.printf(distance[1]+" "+distance[2]+" "+distance[3]+"\n");
            if(distance[1]+distance[2]<=distance[3])
                return -3;
            if(distance[1]==distance[2]||distance[2]==distance[3]||distance[3]==distance[1])
                System.out.printf("true ");
            else
                System.out.printf("false ");
            if(distance[1]==distance[2]&&distance[1]==distance[3]&&distance[3]==distance[2])
                System.out.printf("true");
            else
                System.out.printf("false");
        }
        else if (x == 2) {
            double[] distance = new double [5];
            distance[1]=pointSet[1].DistanceCalculation(pointSet[2]);
            distance[2]=pointSet[1].DistanceCalculation(pointSet[3]);
            distance[3]=pointSet[2].DistanceCalculation(pointSet[3]);
            Arrays.sort(distance,0,4);
            if(distance[1]+distance[2]<=distance[3])

                return -3;
            System.out.printf(printDouble(distance[1]+distance[2]+distance[3])+" "+printDouble(Math.sqrt((distance[1]+distance[2]+distance[3])*(distance[1]+distance[2]-distance[3])*(distance[1]+distance[3]-distance[2])*(distance[2]+distance[3]-distance[1]))/4)+" "+printDouble((pointSet[1].x+pointSet[2].x+pointSet[3].x)/3)+","+printDouble((pointSet[1].y+pointSet[2].y+pointSet[3].y)/3));

        }
        else if (x == 3) {//判断是啥三角形
            double[] distance = new double [5];
            distance[1] = pointSet[1].DistanceCalculation(pointSet[2]);
            distance[2] = pointSet[1].DistanceCalculation(pointSet[3]);
            distance[3] = pointSet[2].DistanceCalculation(pointSet[3]);
            Arrays.sort(distance,0,4);
            if(distance[1]+distance[2]<=distance[3])
                return -3;


            if((int)(distance[1]*distance[1])+(int)(distance[2]*distance[2])==(int)(distance[3]*distance[3]))
                System.out.printf("false true false");
            else if(distance[1]*distance[1]+distance[2]*distance[2]>distance[3]*distance[3])
                System.out.printf("false false true");
            else
                System.out.printf("true false false");
        }
        else if (x == 4) {
            if(pointSet[1].x==pointSet[2].x&&pointSet[1].y==pointSet[2].y) {
                System.out.printf("points coincide");
                return 5;
            }
            double[] distance = new double [5];
            if((pointSet[5].x==pointSet[3].x&&pointSet[3].x==pointSet[4].x)||(pointSet[5].y==pointSet[3].y&&pointSet[3].y==pointSet[4].y))
                return -3;
            line.a=pointSet[1];line.b = pointSet[2];
//            for(int i=1;i<=5;i++)
//                System.out.printf(pointSet[i].x+" "+pointSet[i].y+"\n");
            Triangle tri = new Triangle();
            tri.a = new Line();
            tri.b = new Line();
            tri.c = new Line();
            tri.a.a = pointSet[3];tri.a.b = pointSet[4];
            tri.b.a = pointSet[3];tri.b.b = pointSet[5];
            tri.c.a = pointSet[4];tri.c.b = pointSet[5];
            int num = 0;
          //  System.out.printf(line.judgeIntersection(tri.a)+" "+line.judgeIntersection(tri.b)+" "+line.judgeIntersection(tri.c)+"\n");
            if(line.judgeIntersection(tri.a)==1)
                num++;
            if(line.judgeIntersection(tri.b)==1)
                num++;
            if(line.judgeIntersection(tri.c)==1)
                num++;
            if(num==0) {
                System.out.printf("0");
                return  5;
            }
            if(num==1||(num==2&&(line.sameIntersection(tri.c, tri.a)||line.sameIntersection(tri.b, tri.a)||line.sameIntersection(tri.c, tri.b)))){
                System.out.printf("1");
                return 5;
            }
            System.out.printf("2 ");
            double s = tri.area(),s2=0;
            if(line.judgeIntersection(tri.c)==-1|| line.sameIntersection(tri.c, tri.a)|| line.sameIntersection(tri.b, tri.c)){
                s2 = areaCalculation(pointSet[3],pointSet[4],pointSet[5],line,s);
              //  System.out.printf(1+"\n");
            }
                
            else if(line.judgeIntersection(tri.b)==-1||line.sameIntersection(tri.a, tri.b)){
                s2=  areaCalculation(pointSet[4],pointSet[3],pointSet[5],line,s);
               // System.out.printf(2+"\n");
            }
                
            else{
                s2 = areaCalculation(pointSet[5],pointSet[4],pointSet[3],line,s);
              //  System.out.printf(3+"\n");
            }
                
          //  System.out.printf(s2+" ");
            System.out.printf(printDouble(Math.min(s2,s-s2))+" "+printDouble(Math.max(s2,s-s2)));
        }
        else if (x == 5) {
            double[] distance = new double [5];
            if((pointSet[2].x==pointSet[3].x&&pointSet[3].x==pointSet[4].x)||(pointSet[2].y==pointSet[3].y&&pointSet[3].y==pointSet[4].y))
                return -3;
            Triangle a= new Triangle(),b= new Triangle(),c= new Triangle(),d= new Triangle();
            a.b= new Line();a.a= new Line();a.c = new Line();
            b.b= new Line();b.a= new Line();b.c = new Line();
            c.b= new Line();c.a= new Line();c.c = new Line();
            d.b= new Line();d.a= new Line();d.c = new Line();
            a.a.a=pointSet[2];a.a.b = pointSet[3];
            a.b.a=pointSet[2];a.b.b = pointSet[4];
            a.c.a=pointSet[4];a.c.b = pointSet[3];
            b.a.a=pointSet[1];b.a.b = pointSet[3];
            b.b.a=pointSet[1];b.b.b = pointSet[4];
            b.c.a=pointSet[4];b.c.b = pointSet[3];
            c.a.a=pointSet[2];c.a.b = pointSet[1];
            c.b.a=pointSet[2];c.b.b = pointSet[4];
            c.c.a=pointSet[4];c.c.b = pointSet[1];
            d.a.a=pointSet[2];d.a.b = pointSet[3];
            d.b.a=pointSet[2];d.b.b = pointSet[1];
            d.c.a=pointSet[1];d.c.b = pointSet[3];
            if(d.area()==0||b.area()==0||c.area()==0)
                System.out.println("on the triangle");
            else if(Math.abs(a.area()-b.area()-c.area()-d.area())<0.0005)
                System.out.printf("in the triangle");
            else
                System.out.println("outof the triangle");



        }

        return 5;
    }
}

case4卡我巨久hhhhh
其他到时还好，如果不用类封装真的会写到死