在Java中用ArrayList按升序插入对象

Question

public class Polynomial
{

   private ArrayList<Term> polynomials ;

   /**
     * Creates a new Polynomial object with no terms
     */
  public Polynomial()
  {
       polynomials = new ArrayList<>() ;
  }

  /**
    * Inserts a new term into its proper place in a Polynomial
    * @param coeff the coefficient of the new term
    * @param expo the exponent of the new term
    */
   public void insert(int coeff, int expo)
   {

      Term newTerm = new Term (coeff, expo) ; 


      if (polynomials.isEmpty())
      {
          polynomials.add(newTerm);
          return;
      }


      int polySize = polynomials.size() - 1 ;


      for (int i = 0 ; i <= polySize ; i++)
      {
            Term listTerm = polynomials.get(i) ;  
            int listTermExpo = listTerm.getExpo() ;

            if ( expo <= listTermExpo )
            {
                 polynomials.add(i, newTerm);
                 return;
            }

            else if ( expo > listTermExpo )
           {
                 polynomials.add(newTerm) ;
                 return ;
           }

    }

}

for (i = polySize ; i >= 0 ; i--)
{
  etc.
}

另外，我应该提到，我不允许使用任何其他集合或类，所以我必须使用for、if、else或do while语句来执行此操作。提前感谢！

Answer 1

从for循环中移除以下内容：

       else if (expo > listTermExpo)
       {
             polynomials.add(newTerm);
             return;
       }

将其放置在for循环之后：

polynomials.add(newTerm);
return;

推理：只有当这个词不小于列表中的任何一个词时，你才想把它添加到列表的末尾--而不仅仅是第一个词。