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A. Black-and-White Cube

time limit per test

0.5 secondsmemory limit per test

256 megabytesinput

standard inputoutput

standard outputYou are given a cube of size *k* × *k* × *k*, which consists of unit cubes. Two unit cubes are considered neighbouring, if they have common face.

Your task is to paint each of *k*^{3} unit cubes one of two colours (black or white), so that the following conditions must be satisfied:

- each white cube has exactly 2 neighbouring cubes of white color;
- each black cube has exactly 2 neighbouring cubes of black color.

Input

The first line contains integer *k* (1 ≤ *k* ≤ 100), which is size of the cube.

Output

Print -1 if there is no solution. Otherwise, print the required painting of the cube consequently by layers. Print a *k* × *k* matrix in the first *k* lines, showing how the first layer of the cube should be painted. In the following *k* lines print a *k* × *k* matrix — the way the second layer should be painted. And so on to the last *k*-th layer. Note that orientation of the cube in the space does not matter.

Mark a white unit cube with symbol "w" and a black one with "b". Use the format of output data, given in the test samples. You may print extra empty lines, they will be ignored.

Examples

Input

1

Output

-1

Input

2

Output

bb

ww

bb

ww

Codeforces (c) Copyright 2010-2018 Mike Mirzayanov

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