需要幫助：計算機科學101硬件/ JAVA

Question

我在標題中編寫了問題代碼，似乎遇到了一些問題。任何人都可以給我一些見解或提示我做錯了什麼。特別是使用代碼的「if ... else」部分。

以下是問題＃9。如果您點擊鏈接，它會向您顯示問題的打印輸出。 http://s21.postimg.org/nl2tmf5tj/Screen_Shot_2013_09_21_at_6_44_46_PM.png

這裏是我的代碼：

import java.util.*; 
public class Ch3Ex9 { 
/** 
* This method asks user for an x,y coordinates of a point, then returns the 
* distance to the origin and which quadrant the point is in. 
*/ 
public static void main(String[] args) 
{ 
    double xCoord; //x Coordinant initialized to 3 
    double yCoord; //y Coordinant initalized to 4 
    double hypo; //hypotenuse 

    //declare an instance of Scanner to read the datastream from the keyboard 
    Scanner keyboard = new Scanner(System.in); 

    //get x Coordinant from the user 
    System.out.print("Please enter the X coordinant: "); 
    xCoord = keyboard.nextDouble(); 

    //get Y Coordinate from the user 
    System.out.print("Please enter the Y coordinant: "); 
    yCoord = keyboard.nextDouble(); 

    //calculate the hypotenuse which is the length to the origin 
    hypo = Math.hypot(xCoord, yCoord); 
      System.out.println("The hypotenuse is "+hypo); 

    //determine which Quadrant the user-inputted point resides in 
    if (xCoord>0) && (yCoord>0) // 
     System.out.println("Point lies in Quadrant I."); 
    else if (xCoord<0) && (yCoord>0) 
     System.out.println("Point lies in Quadrant II."); 
    else if (xCoord<0) && (yCoord<0) 
     System.out.println("Point lies in Quadrant III."); 
    else if (xCoord>0) && (yCoord<0) 
     System.out.println("Point lies in Quadrant IV.") 
    } 
} 

Answer 1

有太多的括號內。更改

if (xCoord>0) && (yCoord>0) 

到

if (xCoord>0 && yCoord>0) 

，同樣與他人。