h = int(1.4142 * 10 ** 4.5) ans = [] s = x = 0 for i in range(h, -1, -1): s += i x += 1 ans.append([x,s]) for i in range(1, h+1): s -= i x += 1 ans.append([x,s]) s = 0 for i in range(h, -1, -1): s += i x -= 1 ans.append([x,-s]) for i in range(1, h+1): s -= i x -= 1 ans.append([x,-s]) print(len(ans)) for row in ans: print(*row) print() import sys sys.stdout.flush()