Black-and-white cube

You are given a cube with dimensions (k $\times$ k $\times$ k), composed of unit cubes. Two unit cubes are considered adjacent if they share a face.

Your task is to color each of the (k^3) unit cubes using one of two colors: black or white. The coloring must satisfy the following conditions:

• Each white cube must have exactly 2 adjacent cubes that are also white.

• Each black cube must have exactly 2 adjacent cubes that are also black.

Input

The input consists of a single integer (k) ((1 $\le$ k $\le$ 100)) — the size of the cube.

Output

If no valid coloring exists, output -1. Otherwise, provide the coloring of the cube layer by layer. For the first k lines, output the (k $\times$ k) matrix representing the first layer of the cube. For the next k lines, output the (k $\times$ k) matrix for the second layer, and continue in this manner until the k-th and final layer.

Use the symbol "w" to denote a white unit cube and "b" for a black unit cube. Follow the output format as demonstrated in the test examples.

Examples