#include <iostream>
#include <algorithm>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <iomanip>
#include <cmath>
#include <complex>
using namespace std;
using ll = long long;
#define rep(i, j, n) for(int i = j; i < (int)n; ++i)

constexpr ll MOD = 1000000007;
constexpr ll INF = 1LL << 60;
using namespace std;

class Enumeration {
public:
	explicit Enumeration(int n, uint64_t mod) : fact(n), inv(n), finv(n), mod(mod) {
		fact[0] = finv[0] = fact[1] = inv[1] = finv[1] = 1;
		for (int i = 2; i < n; ++i) {
			fact[i] = fact[i - 1] * i % mod;
			inv[i] = mod - inv[mod % i] * (mod / i) % mod;
			finv[i] = finv[i - 1] * inv[i] % mod;
		}
	}
	uint64_t comb(int n, int k) {
		if (n < k || n < 0 || k < 0) return 0;
		return fact[n] * finv[n - k] % mod * finv[k] % mod;
	}
	uint64_t modpow(uint64_t x, uint64_t e) {
		uint64_t res = 1;
		while (e > 0) {
			if (e & 1) res = res * x % mod;
			x = x * x % mod;
			e >>= 1;
		}
		return res;
	}

private:
	uint64_t mod;
	vector<uint64_t> fact, inv, finv;
};


int main() {
	cin.tie(0);
	ios_base::sync_with_stdio(0);
	ll n, m; cin >> n >> m;
	Enumeration e(m + 1, MOD);

	ll ans = 0;
	rep(i, n, m + 1) ans = (ans + e.comb(i, n)) % MOD;
	cout << ans << endl;
	return 0;
}