class Demo13
{
public static void main (String[] args)
{ int a=1;
while (a<=5) //while
{
System.out.println("hello world!") ;
a++;//++就是加1
}
}
}
class Demo13
{
public static void main (String[] args)
{
int b =1;
do{
System.out.println("hello world!");
b++;
}
while(b<=5);
}
}