import java.io.*;
import java.util.*;
import java.math.*;

public class grid
{
  public static void main(String[] args) throws Exception
  {
    BufferedReader br = new BufferedReader(new FileReader("grid.in"));
    StringTokenizer st;
    String line;
    int m = 0;
    int n = 0;
    BigInteger[] lut = new BigInteger[65];
    
	lut[0] = new BigInteger("1");
	for (int i = 1; i < 65; i++) lut[i] = lut[i-1].multiply(new BigInteger(Integer.toString(i)));
    while (!(line = br.readLine()).equals("0 0"))
    {
      st = new StringTokenizer(line);
      if (st.hasMoreTokens()) m = Integer.parseInt(st.nextToken());
      if (st.hasMoreTokens()) n = Integer.parseInt(st.nextToken());
      System.out.println(lut[m + n].divide(lut[m].multiply(lut[n])));
    }
  }
 
}