#pragma GCC optimize ("O3")
#pragma GCC target ("sse4")
#include<stdio.h>
#include<iostream>
#include<vector>
#include<algorithm>
#include<string>
#include<string.h>

#ifdef LOCAL
#define eprintf(...) fprintf(stderr, __VA_ARGS__)
#else
#define NDEBUG
#define eprintf(...) do {} while (0)
#endif
#include<cassert>

using namespace std;

typedef long long LL;
typedef vector<int> VI;

#define REP(i,n) for(int i=0, i##_len=(n); i<i##_len; ++i)
#define EACH(i,c) for(__typeof((c).begin()) i=(c).begin(),i##_end=(c).end();i!=i##_end;++i)

template<class T> inline void amin(T &x, const T &y) { if (y<x) x=y; }
template<class T> inline void amax(T &x, const T &y) { if (x<y) x=y; }
#define rprintf(fmt, begin, end) do { const auto end_rp = (end); auto it_rp = (begin); for (bool sp_rp=0; it_rp!=end_rp; ++it_rp) { if (sp_rp) putchar(' '); else sp_rp = true; printf(fmt, *it_rp); } putchar('\n'); } while(0)
template<unsigned MOD_> struct ModInt {
    static constexpr unsigned MOD = MOD_;
    unsigned x;
    void undef() { x = (unsigned)-1; }
    bool isnan() const { return x == (unsigned)-1; }
    inline int geti() const { return (int)x; }
    ModInt() { x = 0; }
    ModInt(int y) { if (y<0 || (int)MOD<=y) y %= (int)MOD; if (y<0) y += MOD; x=y; }
    ModInt(unsigned y) { if (MOD<=y) x = y % MOD; else x = y; }
    ModInt(long long y) { if (y<0 || MOD<=y) y %= MOD; if (y<0) y += MOD; x=y; }
    ModInt(unsigned long long y) { if (MOD<=y) x = y % MOD; else x = y; }
    ModInt &operator+=(const ModInt y) { if ((x += y.x) >= MOD) x -= MOD; return *this; }
    ModInt &operator-=(const ModInt y) { if ((x -= y.x) & (1u<<31)) x += MOD; return *this; }
    ModInt &operator*=(const ModInt y) { x = (unsigned long long)x * y.x % MOD; return *this; }
    ModInt &operator/=(const ModInt y) { x = (unsigned long long)x * y.inv().x % MOD; return *this; }
    ModInt operator-() const { return (x ? MOD-x: 0); }

    ModInt inv() const { return pow(MOD-2); }
    ModInt pow(long long y) const {
	ModInt b = *this, r = 1;
	if (y < 0) { b = b.inv(); y = -y; }
	for (; y; y>>=1) {
	    if (y&1) r *= b;
	    b *= b;
	}
	return r;
    }

    friend ModInt operator+(ModInt x, const ModInt y) { return x += y; }
    friend ModInt operator-(ModInt x, const ModInt y) { return x -= y; }
    friend ModInt operator*(ModInt x, const ModInt y) { return x *= y; }
    friend ModInt operator/(ModInt x, const ModInt y) { return x *= y.inv(); }
    friend bool operator<(const ModInt x, const ModInt y) { return x.x < y.x; }
    friend bool operator==(const ModInt x, const ModInt y) { return x.x == y.x; }
    friend bool operator!=(const ModInt x, const ModInt y) { return x.x != y.x; }
};

constexpr LL MOD = 1000000007;
using Mint = ModInt<MOD>;


int N;
int A[100011];

void MAIN() {
    scanf("%d", &N);
    REP (i, N) scanf("%d", A+i);
    sort(A, A+N);

    Mint ans = 1;
    int prv = 0;
    REP (i, N) {
	ans *= A[i] - prv + 1;
	prv = A[i];
    }

    printf("%d\n", ans.geti());
}

int main() {
    int TC = 1;
//    scanf("%d", &TC);
    REP (tc, TC) MAIN();
    return 0;
}


#define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define rep(i, n) for (ll i = 0; i < (ll)(n); i++)
#define repab(i, a, b) for (ll i = (ll)(a); i < (ll)(b); i++)
#define repr(i, n) for (ll i = (ll)(n); i >= 0; i--)
#define vsort(v) sort(v.begin(), v.end())
#define vsortr(v) sort(v.rbegin(), v.rend())

//定数
#define INF32 2147483647           // 2.147483647×10^{9}:32bit整数のinf
#define INF64 9223372036854775807  // 9.223372036854775807×10^{18}:64bit整数のinf
#define MOD 1000000007             //問題による

int main() {
  ll a, b;
  cin >> a >> b;

  ll ans = 0;
  if (a + b >= 15 && b >= 8) {
    ans = 1;
  } else if (a + b >= 10 && b >= 3) {
    ans = 2;
  } else if (a + b >= 3) {
    ans = 3;
  } else {
    ans = 4;
  }
  cout << ans << endl;
}
