There is a building with n rooms, numbered 1 to n.

We can move from any room to any other room in the building.

Let us call the following event a move: a person in some room i goes to another room j~ (i \neq j).

Initially, there was one person in each room in the building.

After that, we know that there were exactly k moves happened up to now.

We are interested in the number of people in each of the n rooms now. How many combinations of numbers of people in the n rooms are possible?

Find the count modulo (10^9 + 7).

Constraints

* All values in input are integers.
* 3 \leq n \leq 2 \times 10^5
* 2 \leq k \leq 10^9

Input

Input is given from Standard Input in the following format:


n k


Output

Print the number of possible combinations of numbers of people in the n rooms now, modulo (10^9 + 7).

Examples

Input

3 2


Output

10


Input

200000 1000000000


Output

607923868


Input

15 6


Output

22583772
import java.util.*;

public class Main {
    static int MAX = 10010017;  // (1 ≦ k ≦ n ≦ 10^7 程度)
    static int MOD = 1000000007;
    static long[] fac;  // 階乗
    static long[] finv;
    static long[] inv;  // 逆元
    
    public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        COMinit();
        int n = sc.nextInt();
        int k = sc.nextInt();
        k = Math.min(k, n - 1);
        
        long ans = 0;
        for (int i = 0; i <= k; i++) {
            ans = ans + (nCkMOD(n, i) * nCkMOD(n - 1, i)) % MOD;
            ans %= MOD;
        }
        
        System.out.println(ans);
    }
    
    // テーブルを作る前処理
    public static void COMinit() {        
        fac = new long[MAX];
        finv = new long[MAX];
        inv = new long[MAX];
        
        fac[0] = fac[1] = 1;
        finv[0] = finv[1] = 1;
        inv[1] = 1;
        for (int i = 2; i < MAX; i++){
            fac[i] = fac[i - 1] * i % MOD;
            inv[i] = MOD - inv[MOD%i] * (MOD / i) % MOD;
            finv[i] = finv[i - 1] * inv[i] % MOD;
        }
    }
    
    // 二項係数計算(1 ≦ k ≦ n ≦ 10^7 程度)
    public static long nCkMOD(int n, int k){
        if (n < k) return 0;
        if (n < 0 || k < 0) return 0;
        return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;
    }
    
    public static long modpow(long a, long n) {
        long res = 1;
        while (n > 0) {
            long tmp = n & 1;
            if (tmp > 0) res = res * a % MOD;
            a = a * a % MOD;
            n >>= 1;
        }
        return res;
    }
}