3495：Bitwise XOR of Arithmetic Progression

Write a program that, given three positive integers x, y and z (x, y, z < 2³², x ≤ y), computes the bitwise exclusive disjunction (XOR) of the arithmetic progression x, x + z, x + 2z, …, x + kz, where k is the largest integer such that x + kz ≤ y.

The input contains multiple test cases. Each test case consists of three integers x, y, z separated by single spaces on a separate line. There are neither leading or trailing blanks nor empty lines. The input ends once EOF is met.

For each test case, output the value of __poj_jax_start__\bigoplus_{k=0}^{\lfloor(y-x)/z\rfloor}x+kz__poj_jax_end__ on a separate line. There should be neither leading or trailing spaces nor empty lines.