1.
public class Test
{
public static void main(String[] args)
{
int s=0;
for(int i=1;i<=4;i++)
s+=i;
System.out.println("1+2+3+4="+s);
}
}
2.
import java.util.Scanner;
public class Test
{
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
int n;
System.out.print("请输入一个数:");
n=sc.nextInt();
if(0==n%2)
System.out.println(""+n+"是偶数");
else
System.out.println(""+n+"是奇数");
sc.close();
}
}
3.
import java.awt.*;
import javax.swing.*;
public class Demo extends JFrame
{
public static void main(String[] args)
{
new Demo();
}
Demo()
{
setSize(300,400);
setX(300);
setY(200);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
}
}
追问好的 谢谢
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