import java.util.Scanner;
/**
* HJ91 走方格的方案数
*/
public class HJ091 {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
while (sc.hasNextInt()) {
int m = sc.nextInt();
int n = sc.nextInt();
System.out.println(cal(m, n));
}
sc.close();
}
private static int cal(int m, int n) {
if (m == 1 || n == 1) {
return m + n;
}
return cal(m - 1, n) + cal(m, n - 1);
}
}