什么是页面的定界符

public class Wb2
{
public static void main(string[] asddfsdf)
{
Print();
}

public Print()
{
int num = nwe int[100];

for(int a = 0; a < 100; a++ )
{
Math.random(a);
System.out.print(num[a]);
if(a %10 == 0)
{
System.out.print("\n");
}
}
}
}