XOR

You are given numbers $n$, $x$ and a sequence of $n$ numbers. Find the largest possible interval of consequently following elements, such that xor of these elements is not less than $x$. I.e., more formally, find such $i$ and $k$ that

and $k$ is largest possible positive number.

It's guaranteed that for each test from the testset such an interval exists.

We remind you that xor operation is applied to numbers in binary representation, so that for each pair of bits the following is true:

0 \text{ xor } 0 = 0

0 \text{ xor } 1 = 1

1 \text{ xor } 0 = 1

1 \text{ xor } 1 = 0

The result of this operation doesn't depend on the order of operands a \text{ xor } b = b \text{ xor } a. Moreover (a \text{ xor } (a \text{ xor } b)) = b.

In Pascal this operation is represented as xor. In C/C++/Java as ^.