import static java.lang.System.out; import java.util.Scanner; import java.io.File; import java.io.IOException; class Main { public static void main(String[] args) throws IOException { Scanner s = new Scanner(new File("play.dat")); while(s.hasNextInt()) { int magnitude = s.nextInt(); out.println(play(magnitude)); if(s.hasNextInt()) out.println(); } } // 3 => 1 3 5 3 1 (5) // 4 => 1 3 5 7 5 3 1 (7) // 5 => 1 3 5 7 9 7 5 3 1 (9) // https://www.desmos.com/calculator/0gszz81jpx // m = 2x - 1 (top) // y = m - 2 * abs(x - ((m + 1) / 2)) public static String play(int mag) { int[] counts = new int[(mag * 2) - 1]; String[] sequence = new String[counts.length]; for(int i = 1; i <= counts.length; i++) counts[i - 1] = counts.length - (2 * Math.abs(i - (counts.length + 1) / 2)); for(int i = 0; i < counts.length; i++) sequence[i] = repeat("*", counts[i]); return String.join("\n", sequence); } public static String repeat(String sub, int n) { String result = ""; for(int i = 0; i < n; i++) result += sub; return result; } }