你好世界，

public class HelloWorld
{
public static void main(String []args)
{
System.out.println("hello! world");
}
}

三个数比大小，java初试

import java.util.Scanner;
public class Max
{
public static void main(String []args)
{
Scanner sc= new Scanner(System.in);
System.out.println("please input the first int num");
int num1=sc.nextInt();
System.out.println("please input the second int num");
int num2=sc.nextInt();
System.out.println("please input the three int num");
int num3=sc.nextInt();
int max=num1;
if(max<num2)
{
max=num2;
}
if(max<num3)
{
max=num3;
}
System.out.println("max("+num1+","+num2+","+num3+")"+"="+max);

9*9 乘法表  java乘法表

public class multtable
{
public static void main (String []args)
{
for(int i=1;i<=9;i++)
{
for(int j=1;j<=i;j++)
{
System.out.print(j+"*"+i+"="+j*i+" ");
}
System.out.println();
}
}
}