relocatable address

The address generated by the compiler are relocatable addresses.
See : Introduction to computer-based imaging systems By Divyendu Sinha, Edward R. Dougherty , page.213 :

Assuming the page size as 64 KB (2¹⁶):
The compiler generated relocatable addresses as if the entire program were to be loaded at once. The page number and offset can be easily computed from the relocatable address. Since the offset must be a nonnegative number smaller than the page size, the offset is the least significant 16 bits of the relocatable address. The remaining 25-16 = 9 bits specify the page number. Consider the relocatable address 145678. Since

145678 (decimal) = 0 00000010 00111001 00001110 (binary),
we have the page number as 2 (or 000000010 in binary) and the offset as 14,606( or 0011100100001110 in binary).

If the page size is changed later on to 32KB, programs need not be recompiled to run on the system. Computation of page number and offset is done by the memory manager

Basic introduction to probability

Surprisingly the basic introduction to probability was found in a biology book!
Here is the summary:
Product Rule:
When two or more events are independent, the probability that they will occur in succession is calculated using the product rule--their individual probabilities are multiplied. Ex : probability of getting two heads in succession is 1/2 x 1/2 = 1/4

Sum Rule:
Sum Rule is applied when there are two or more different ways of obtaining the same outcome; that is, the probability tat either event A or event B will occur equals P(A) + P(B)

Source: Billogy: Te dynamic science by Peter Russell p.240

reversing a linked list

Few of the most elegant solutions for reversing a linked list:
1. Stanford : Linked list problems
2. Algorithms : 4th Edition : Stacks and Queues
The code is reproduced here and is very elegant:

public Node reverse(Node first) {
    if (first == null || first.next == null) return first;
    Node second = first.next;
    Node rest = reverse(second);
    second.next = first;
    first.next  = null;
    return rest;
}