three=one+two;有什么用?

public class HelloWorld{

    public static void main(String[] args) {

   int one = 10 ;

        int two = 20 ;

        int three = 0 ;

        System.out.println("three+=one==>"+40);

        System.out.println("three-=one==>"+30);

        System.out.println("three*=one==>"+300);

同样可以输出

three+=one==>40
three-=one==>30
three*=one==>300