public class Main {
    public static void main(String[] args) {
        dfs(1, 9, 16);
        System.out.println(sum);
    }

    static int sum = 0;

    static void dfs(int x, int a, int b) {
        if (x == 8) {
            if (a == 0 && b == 0) {
                //如果七个人恰好分完则计数加一
                sum++;
            }
            return;
        }

        for (int i = 0; i <= a; i++) {
            for (int j = 0; j <= b; j++) {
                if (i + j >= 2 && i + j <= 5) {
                    //只有满足2-5的条件才可以
                    dfs(x + 1, a - i, b - j);
                }
            }
        }
    }
}