#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; #define REP(i, n) for (int (i) = 0; (i) < (n); (i)++) #define FOR(i, a, b) for (int (i) = (a); (i) < (b); (i)++) #define RREP(i, a) for(int (i) = (a) - 1; (i) >= 0; (i)--) #define FORR(i, a, b) for(int (i) = (a) - 1; (i) >= (b); (i)--) #define DEBUG(C) cerr << #C << " = " << C << endl; using LL = long long; using VI = vector; using VVI = vector; using VL = vector; using VVL = vector; using VD = vector; using VVD = vector; using PII = pair; using PDD = pair; using PLL = pair; using VPII = vector; template using VT = vector; #define ALL(a) begin((a)), end((a)) #define RALL(a) rbegin((a)), rend((a)) #define SORT(a) sort(ALL((a))) #define RSORT(a) sort(RALL((a))) #define REVERSE(a) reverse(ALL((a))) #define MP make_pair #define FORE(a, b) for (auto &&a : (b)) #define FIND(s, e) ((s).find(e) != (s).end()) #define EB emplace_back const int INF = 1e9; const int MOD = INF + 7; const LL LLINF = 1e18; LL N, K; VL a; void outbin(int n, int size) { string res = ""; while (n) res += n % 2 + '0', n /= 2; while (res.length() != size) res += '0'; REVERSE(res); cout << res << endl; } #if 1 int main(void) { cin >> N >> K; a.resize(K); REP(i, K) cin >> a[i]; SORT(a); LL ans = 1; if (K == 0) { REP(i, N) (ans *= (i + 1)) %= MOD; cout << ans <