import java.util.*;

@SuppressWarnings("unused")
public class Main {

  private static void solve() {
    long n = nl();
    int m = ni();
    int mod = 998244353;

    if (n < m) {
      System.out.println(0);
      return;
    }

    long ret = pow(2, n, mod);;
    // nCm + nCm+1 + nCm+2 ...
    // = 2^n - nC0 - nC1 - .. - nCm-1

    long x = 1;
    for (int i = 0; i < m; i ++) {
      ret = (ret + mod - x) % mod;

      x *= (n + mod - i) % mod;
      x %= mod;
      x *= inv(i + 1, mod);
      x %= mod;
    }

    System.out.println(ret);
  }

  public static long inv(long a, int p) {
      long ret = 1;
      long mul = a;
      for (long n = p - 2; n > 0; n >>>= 1) {
          if ((n & 1) == 1)
              ret = ret * mul % p;
          mul = mul * mul % p;
      }
      return ret;
  }

  public static long pow(long x, long n, long m) {
      assert (n >= 0 && m >= 1);
      long ans = 1;
      while (n > 0) {
          if (n % 2 == 1)
              ans = (ans * x) % m;
          x = (x * x) % m;
          n /= 2;
      }
      return ans;
  }

  public static void main(String[] args) {
    new Thread(null, new Runnable() {
      @Override
      public void run() {
        long start = System.currentTimeMillis();
        String debug = args.length > 0 ? args[0] : null;
        if (debug != null) {
          try {
            is = java.nio.file.Files.newInputStream(java.nio.file.Paths.get(debug));
          } catch (Exception e) {
            throw new RuntimeException(e);
          }
        }
        reader = new java.io.BufferedReader(new java.io.InputStreamReader(is), 32768);
        solve();
        out.flush();
        tr((System.currentTimeMillis() - start) + "ms");
      }
    }, "", 64000000).start();
  }

  private static java.io.InputStream is = System.in;
  private static java.io.PrintWriter out = new java.io.PrintWriter(System.out);
  private static java.util.StringTokenizer tokenizer = null;
  private static java.io.BufferedReader reader;

  public static String next() {
    while (tokenizer == null || !tokenizer.hasMoreTokens()) {
      try {
        tokenizer = new java.util.StringTokenizer(reader.readLine());
      } catch (Exception e) {
        throw new RuntimeException(e);
      }
    }
    return tokenizer.nextToken();
  }

  private static double nd() {
    return Double.parseDouble(next());
  }

  private static long nl() {
    return Long.parseLong(next());
  }

  private static int[] na(int n) {
    int[] a = new int[n];
    for (int i = 0; i < n; i++)
      a[i] = ni();
    return a;
  }

  private static char[] ns() {
    return next().toCharArray();
  }

  private static long[] nal(int n) {
    long[] a = new long[n];
    for (int i = 0; i < n; i++)
      a[i] = nl();
    return a;
  }

  private static int[][] ntable(int n, int m) {
    int[][] table = new int[n][m];
    for (int i = 0; i < n; i++) {
      for (int j = 0; j < m; j++) {
        table[i][j] = ni();
      }
    }
    return table;
  }

  private static int[][] nlist(int n, int m) {
    int[][] table = new int[m][n];
    for (int i = 0; i < n; i++) {
      for (int j = 0; j < m; j++) {
        table[j][i] = ni();
      }
    }
    return table;
  }

  private static int ni() {
    return Integer.parseInt(next());
  }

  private static void tr(Object... o) {
    if (is != System.in)
      System.out.println(java.util.Arrays.deepToString(o));
  }
}