// Here is a program that illustrates nested loops used in output.
// Note the "triangular" nature of these loops -- this happens when
// one of the bounds (either the lower or upper bound) is an outer loop
// variable instead of a constant.

public class Loop3
{
  public static void main(String [] args)
  {
    int i, j, topNumber;

    // The topNumber determines how big each triangle will be.
    for (topNumber = 20; topNumber <= 40; topNumber += 5)
    {
      // The line number i starts at topNumber, and decrements by 5
      for (i = topNumber; i >= 10; i -= 5)
      {
        // Within a line, we start at j=i, and increment by 5
        for (j = i; j <= topNumber; j += 5)
        {
	    System.out.printf("%d   ", j);
        }
        System.out.printf("\n");
      }
      System.out.printf("\n");
    }
  }
}

/* Here is the output:

20
15   20
10   15   20

25
20   25
15   20   25
10   15   20   25

30
25   30
20   25   30
15   20   25   30
10   15   20   25   30

35
30   35
25   30   35
20   25   30   35
15   20   25   30   35
10   15   20   25   30   35

40
35   40
30   35   40
25   30   35   40
20   25   30   35   40
15   20   25   30   35   40
10   15   20   25   30   35   40

*/