public static void main(String[] args) throws Exception {
int N = 6000;
if (args.length >= 1) N = Integer.parseInt(args[0]);
Crb = new double[N + 7];
Cib = new double[N + 7];
double invN = 2.0 / N;
for (int i = 0; i < N; i++) {
Cib[i] = i * invN - 1.0;
Crb[i] = i * invN - 1.5;
}
yCt = new AtomicInteger();
out = new byte[N][(N + 7) / 8];
Thread[] pool = new Thread[2 * Runtime.getRuntime().availableProcessors()];
for (int i = 0; i < pool.length; i++)
pool[i] =
new Thread() {
public void run() {
int y;
while ((y = yCt.getAndIncrement()) < out.length) putLine(y, out[y]);
}
};
for (Thread t : pool) t.start();
for (Thread t : pool) t.join();
OutputStream stream = new BufferedOutputStream(System.out);
stream.write(("P4\n" + N + " " + N + "\n").getBytes());
for (int i = 0; i < N; i++) stream.write(out[i]);
stream.close();
}
/**
* Checks if address can be reached using one argument InetAddress.isReachable() version or ping
* command if failed.
*
* @param addr Address to check.
* @param reachTimeout Timeout for the check.
* @return {@code True} if address is reachable.
*/
public static boolean reachableByPing(InetAddress addr, int reachTimeout) {
try {
if (addr.isReachable(reachTimeout)) return true;
String cmd = String.format("ping -%s 1 %s", U.isWindows() ? "n" : "c", addr.getHostAddress());
Process myProc = Runtime.getRuntime().exec(cmd);
myProc.waitFor();
return myProc.exitValue() == 0;
} catch (IOException ignore) {
return false;
} catch (InterruptedException ignored) {
Thread.currentThread().interrupt();
return false;
}
}