class CutRectangle { private static int[][] dirs = [[0, -1], [-1, 0], [0, 1], [1, 0]] static void main(String[] args) { cutRectangle(2, 2) cutRectangle(4, 3) } static void cutRectangle(int w, int h) { if (w % 2 == 1 && h % 2 == 1) { return } int[][] grid = new int[h][w] Stack stack = new Stack<>() int half = (int) ((w * h) / 2) long bits = (long) Math.pow(2, half) - 1 for (; bits > 0; bits -= 2) { for (int i = 0; i < half; i++) { int r = (int) (i / w) int c = i % w grid[r][c] = (bits & (1 << i)) != 0 ? 1 : 0 grid[h - r - 1][w - c - 1] = 1 - grid[r][c] } stack.push(0) grid[0][0] = 2 int count = 1 while (!stack.empty()) { int pos = stack.pop() int r = (int) (pos / w) int c = pos % w for (int[] dir : dirs) { int nextR = r + dir[0] int nextC = c + dir[1] if (nextR >= 0 && nextR < h && nextC >= 0 && nextC < w) { if (grid[nextR][nextC] == 1) { stack.push(nextR * w + nextC) grid[nextR][nextC] = 2 count++ } } } } if (count == half) { printResult(grid) } } } static void printResult(int[][] arr) { for (int[] a : arr) { println(Arrays.toString(a)) } println() } }