//FushuTestyichang.java
class LessParamException extends  Exception { 
private int inputNum; //用戶輸入的參數(shù)數(shù)目
public LessParamException(int a)  {inputNum=a;}
public int getInputNum( ) {return inputNum;}
public void handleException( ) {
System.out.println("需要輸入5個參數(shù)，您只輸入了"+getInputNum()+"個參數(shù)，程序中止。請再次運行程序時注意");
}
} 

class NoOpertaionException extends  Exception { //自定義的運算符異常
public NoOpertaionException( ){}
public void handleException( ){
System.out.println("缺乏操作符。請輸入+、-、x、\\ 之一進行運算！");
}
}

class DividedByZeroException extends  Exception  {//自定義除數(shù)為零的異常
public DividedByZeroException( ){ }
public void handleException( ){
System.out.println("除數(shù)為零，請重新輸入除數(shù)！");
}
}

class Fushu{ //復數(shù)類
	private float x,y;
	public float getShibu(float x){ return x;} //獲得實部方法
	public float getXubu(float y){ return y;}//獲得虛部方法
	    
   public String showFushu( ) { return x+"+"+y+"i"; }//顯示復數(shù)
	      
   public Fushu add(Fushu f){//加法
		float a=this.x+f.x;
		float b=this.y+f.y;
		Fushu Result=new Fushu(a,b);
		return Result; }
	        
   public Fushu minus(Fushu f){//減法
		 float a=this.x-f.x;
		 float b=this.y-f.y;
		 Fushu Result=new Fushu(a,b);
		 return Result; }
	
   public Fushu mult(Fushu f){//乘法
      	 float a=this.x*f.x-this.y*f.y;
      	 float b=this.x*f.y+this.y*f.x;
      	 Fushu Result=new Fushu(a,b);
		 return Result; }
	    
 	public Fushu divd(Fushu f) throws  DividedByZeroException {//除法，聲明拋出除數(shù)為0異常
		 if(f.x==0) throw new DividedByZeroException(); //若除數(shù)為0則拋出異常
        else {
float a=(this.x*f.x+this.y*f.y)/(f.x*f.x+f.y*f.y);
          float b=(this.y*f.x-this.x*f.y)/(f.x*f.x+f.y*f.y);
        	Fushu Result=new Fushu(a,b);
		    return Result;}
 	}
	public Fushu(float x,float y){//復數(shù)的構造方法
	    this.x=x;
	    this.y=y;}
}

public class FushuTestyichang {//主類
	public static void main(String[] args){
	  try{
		if (args.length<5) throw new LessParamException(args.length);//拋出缺少參數(shù)異常
	   //以下將args參數(shù)轉(zhuǎn)換為float型后，構造出2個復數(shù)對象并顯示：
Fushu f1=new Fushu(Float.parseFloat(args[0]), Float.parseFloat(args[1]));
    	Fushu f2=new Fushu (Float.parseFloat(args[2]), Float.parseFloat(args[3]
));
		System.out.println("您輸入的復數(shù)是：");
		System.out.println("f1="+f1.showFushu());  //顯示復數(shù)
       System.out.println("f2="+f2.showFushu());  //顯示復數(shù)
	   //以下判斷運算符
if (args[4].equals("+")) 
  {System.out.println("The sum="+f1.add(f2).showFushu());}   //f1+f2
		else if (args[4].equals("-")) 
{System.out.println("The differs="+f1.minus(f2).showFushu());}   //f1-f2
else if (args[4].equals("x"))  
{System.out.println("The product="+f1.mult(f2).showFushu());}   //f1xf2
		else if (args[4].equals("\\")) 
{System.out.println("The quotient="+f1.divd(f2).showFushu());}  //f1\f2
		else {throw new NoOpertaionException();}//拋出運算符錯誤的異常
 		}
	  catch(LessParamException e1)  {e1.handleException( );}
	  catch(DividedByZeroException e2) {e2.handleException( );}
	  catch(NoOpertaionException e3)  {e3.handleException( ); }
	}
}