Homework Lab 11-21 (2) Class Definition

程式一
程式二
程式三


C:\Program Files\Xinox Software\JCreator LE\MyProjects\lab2\DateTry.java:76: unreported exception java.io.IOException; must be caught or declared to be thrown date.readInput();



C:\Program Files\Xinox Software\JCreator LE\MyProjects\lab2\DateTry.java:78: month has private access in DateTryDemo System.out.println(date.month);

Lab 11-21 (1) Class Definition

class Date{
public String month;
public int day;

public void makeItnewYears()
{
System.out.println(month + " "+day+"!");
}

}
public class ananfish {
public static void main(String[] args)
{ Date date;
date=new Date();
date.month="Jan";
date.day=1;
System.out.println("OUTPUT:");
date.makeItnewYears();

}
}

Homework Lab 10-31 (2) Mean & Variance

import java.io.*;
public class dog
{ public static void main(String args[]) throws IOException
{ String str;
BufferedReader a;
int i=0;
float n,sum=0,sum1=0,j,q;
a=new BufferedReader(new InputStreamReader(System.in));
System.out.println("輸入一個數:");
str=a.readLine(); n=Integer.parseInt(str);
while(n>=0) {
sum=sum+n;
sum1=sum1+(n*n);
i++;
System.out.println("輸入一個數:");
str=a.readLine();
n=Integer.parseInt(str);
}
System.out.println("總值為:"+sum);
System.out.println("E(X)為:"+(float)(sum/i));
System.out.println("E(X*X)為:"+(float)(sum1/i));
System.out.println("又知道variance公式為:E(x*x)-(E(x)*E(x))");
j=(float)(sum/i);
q=(float)(sum1/i);
System.out.println("variance為:"+(q-(j*j)));
}
}

圖檔

Homework 10-31 Lab (1) String Comparison

public class dog
{ public static void main(String args[])
{ String s1="I come from CYCU.";
String s2="I come from cycu.";
if(s1.equals(s2))
System.out.println("They are the same!!");
else
System.out.println("They are different!!");
}
}

http://home.pchome.com.tw/club/savvygirl/dog.JPG
1 ' ==' 只能用在基本的data type而在這裡string產生出來已經是一個object所以要用.equals來看此object 裡面的內容是否相等
2是指有大小寫之分所以如本題是不成立
3是指沒有大小寫之區別