Lnode.java

package PloyItem;  

 /**
*@Author wzy
*@Date 2017年11月12日
*@Version JDK 1.8
*@Description 
*/ 
public class Lnode implements Comparable<Lnode>,Cloneable{  
    public double coef;  
    public int exp;  
    public Lnode next;  
    public Lnode (double coef,int exp){  
        this
 
.exp=exp;  
        this.coef=coef;  
        next=null;  
    }  
    public Lnode(double coef,int exp,Lnode next){  
        this.exp=exp;  
        this.coef=coef;  
        this.next=next;  
    }  
    public boolean equals(Object e){  
        Lnode node=(Lnode)e;  
        return (exp==node.exp);  
    }
    @Override
    protected
 
 Object clone() throws CloneNotSupportedException {
        // TODO Auto-generated method stub
        return super.clone();
    }
    @Override  
    public int compareTo(Lnode o) {  
        // TODO Auto-generated method stub  
        return 0;  
    }  

} 

PloyItemList.java

package PloyItem;

import
 
 java.text.DecimalFormat;
import java.util.Scanner;
/**
 *@Author wzy
 *@Date 2017年11月12日
 *@Version JDK 1.8
 *@Description 
 */
public class PloyItemList  implements Cloneable{  
    private int length;  

    DecimalFormat    df   = new DecimalFormat("######0.0");
    Lnode first;  
    @Override
    protected PloyItemList clone() throws CloneNotSupportedException {
        // TODO Auto-generated method stub
        PloyItemList p=(PloyItemList) super.clone();
        if(this.first!=null) p.first=(Lnode) this.first.clone();
        return p;
    }
    public PloyItemList(int length)  
    {  
        first=null;  
        this.length=length;  
    }  
    public PloyItemList(){  
        first=null;  
        length=0;  
    }  


    public int size()//獲取連結串列的長度  
    {  
        Lnode p=first;  
        int count=0;  
        while(p!=null&&p.coef!=0){  
            count++;  
            p=p.next;  
        }  
        return count;  
    }  
    public boolean add(double coef,int exp)//向連結串列當中新增元素的方法  
    {  

        Lnode p=first,s;  
        s=new Lnode(coef,exp,null);  

        if(first==null){  
            first=s;  
            s.next=null;  
            return true;  
        }  
        else {  
            while(p.next!=null){  
                p=p.next;  
            }  
            p.next=s;  
            s.next=null;  
            return true;  
        }  

    }  
    public boolean add(int coef)//向連結串列當中新增元素的方法  
    {  

        Lnode p=first,s;  
        s=new Lnode(coef,0,null);  
        if(first==null){  
            first=s;  
            s.next=null;  
            return true;  
        }  
        else {  
            while(p.next!=null){  
                p=p.next;  
            }  
            p.next=s;  
            s.next=null;  
            return true;  
        }  
    }  
    public void sort(){//對多項式進行降序排列的方法  
        Lnode p,q;int i,j,m;double n;  
        for( i=0,p=first;i<this.size()-1;i++,p=p.next)  
            for(j=i+1,q=p.next;j<this.size();j++,q=q.next)  
                if(p.exp<q.exp)  
                {  
                    m=p.exp;p.exp=q.exp;q.exp=m;  
                    n=p.coef;p.coef=q.coef;q.coef=n;  
                }  
    }  
    public void union()//對多項式進行合併同類項的方法  
    {  
        Lnode p,q,r;  
        sort();  
        p=first;  
        q=p.next;  
        while(p!=null&& q!=null){  
            if(p.exp==q.exp)  
            {   r=q;  

            p.coef=Double.parseDouble(df.format(p.coef+q.coef));  
            remove(q.coef,q.exp);  
            p=r;  
            q=r.next;  
            }   
            else {  
                p=q;  
                q=q.next;  
            }  
        }  
    }  


    public void remove (double coef,int exp)//刪除連結串列當中的某一個節點的方法  
    {  
        Lnode p=first,q=p;  
        for(q=p;q!=null;q=q.next)  
            if(q.next.coef==coef && q.next.exp==exp)  
                break;  
        q.next=q.next.next;  
    }  


    public String toString()//將連結串列轉化為一個字串輸出的方法  
    {  
        String s="";  
        Lnode p=first;  
        sort();  
        union();  
        while(p!=null){  
            if(p.coef==0)  
                s=s;  
            else if(p.coef==-1&&p.exp>1)
                s=s+"-"+"x^"+p.exp+"+"; 
            else if(p.coef==1)
                s=s+"x"+"x^"+p.exp+"+"; 
            else if(p.exp==0)  
                s=s+p.coef+"+";  
            else if(p.exp==1)  
                s=s+p.coef+"x"+"+";  
            else if(p.next!=null&&p.next.coef<0)
                s=s+p.coef+"x^"+p.exp;
            else  
                s=s+p.coef+"x^"+p.exp+"+";  
            p=p.next;  
        }  
        if(s.contains(".0")&&!s.isEmpty())
            return s.substring(0, s.length()-1).replace(".0", "")+"\n";  
        else if(!s.isEmpty())return s.substring(0, s.length()-1);
        else s="0";return s;
    }  


    public void addPloyItem(PloyItemList p2)//多項式相加的方法  
    {  
        this.sort();p2.sort();  
        Lnode p=this.first,q=p2.first;  
        while(p!=null || q!=null)  
        {  
            if(p!=null && q!=null)  
            {  
                if(p.exp==q.exp){  
                    p.coef+=q.coef;  
                    p=p.next;q=q.next;  
                }  
                else if(p.exp<q.exp){  
                    this.add(q.coef, q.exp);  
                    q=q.next;  
                }  
                else {  
                    this.add(q.coef, q.exp);  
                    q=q.next;  
                }  
            }  
            else if(p==null && q!=null)  
                this.add(q.coef, q.exp);  
            else if(p!=null && q==null)  
                p=p.next;  
        }
    }  


    public void subPloyItem(PloyItemList p2) //多項式相減的方法  
    {
        this.sort();p2.sort();  
        Lnode p=this.first,q=p2.first;  
        while(p!=null || q!=null)  
        {  
            if(p!=null && q!=null)  
            {  
                if(p.exp==q.exp){  
                    p.coef-=q.coef;  
                    p=p.next;q=q.next;  
                }  
                else if(p.exp<q.exp){  
                    this.add(-q.coef, q.exp);  
                    q=q.next;  
                } 
                else {  
                    this.add(-q.coef, q.exp);  
                    q=q.next;  
                }  
            }  
            else if(p==null && q!=null)  
                this.add(-q.coef, q.exp);  
            else if(p!=null && q==null)  
                p=p.next;  
        }
    }
    public double Evaluation(double x) //多項式求值
    {

        this.sort();
        Lnode p=this.first;
        double sum=0;
        while (p!=null) {
            sum+=p.coef*Factorial(x, p.exp);
            p=p.next;
        }
        sum=Double.parseDouble(df.format(sum));
        return sum;

    }
    public PloyItemList Differentiation()//多項式求導
    {
        this.sort();
        Lnode p=this.first;PloyItemList q=new PloyItemList();
        while (p!=null) {
            if(p.exp==0) q.add(0,0);
            if(p.coef*p.exp!=0) q.add(p.coef*p.exp,(p.exp-1));
            p=p.next;
        }
        return q;
    }

    public double Factorial(double x,int y) {
        double m=1;
        while(y>0) {
            m*=x;
            y--;
        }
        return m;
    } 


}

test.java

package PloyItem;

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

public class test {
    public static void main(String[] args) throws CloneNotSupportedException{

        System.out.println("請輸入第一個多項式：");
        PloyItemList p1=shuru();
        PloyItemList s=p1.clone();
        System.out.println("第一個多項式："+"p1(x)="+p1);
        System.out.println(p1.size());
        /*System.out.println("請輸入第二個多項式：");

        PloyItemList p2=shuru();
        System.out.println("第二個多項式："+"p2(x)="+p2);  
        System.out.println("--------------------------------------------");
        System.out.println("第一個多項式："+"p1(x)="+p1); 
        System.out.println("第二個多項式："+"p2(x)="+p2);  

        System.out.println("------------------給定x求值------------------");
        System.out.println("輸入x求p1,p2的值,請輸入x的值:");
        Scanner in=new Scanner(System.in);
        double x=in.nextDouble();
        System.out.println("p1(x="+x+")="+p1.Evaluation(x));
        System.out.println("p2(x="+x+")="+p2.Evaluation(x));
        System.out.println("------------------求導----------------------");
        System.out.println("第一個多項式求導："+"p1'(x)="+p1.Differentiation()); 
        System.out.println("第二個多項式求導："+"p2'(x)="+p2.Differentiation()); 
        System.out.println("--------------------------------------------");
        System.out.println("-----------------加減運算--------------------");
        System.out.println("第一個多項式："+"p1(x)="+p1); 
        System.out.println("第二個多項式："+"p2(x)="+p2);  
        p1.subPloyItem(p2);
        System.out.println("兩個多項式相減："+"p1(x)-p2(x)="+p1);
//      System.out.println(p2);
        p1.addPloyItem(p2);
//      System.out.println(p1);
        p1.addPloyItem(p2);
        System.out.println("兩個多項式相加："+"p1(x)+p2(x)="+p1);*/


    }
    public static PloyItemList shuru(){
        System.out.println("------------------------------------------");
        @SuppressWarnings("resource")
        Scanner sc=new Scanner(System.in);
        List<String> lits=new ArrayList<>();
        while (true) {
            String s=sc.nextLine();
            if(s.equals("0 0")) break;
            lits.add(s);
        }
        PloyItemList p1=new PloyItemList();
        for (String string : lits) {
            String []t=string.split(" ");
            p1.add(Double.parseDouble(t[0]),Integer.parseInt(t[1]));
        }
        System.out.println("------------------------------------------");
        return p1;

    }
}