Submission #163510

# Submission time Handle Problem Language Result Execution time Memory
163510 2019-11-13T16:00:29 Z iefnah06 Asceticism (JOI18_asceticism) C++11
100 / 100
14 ms 1400 KB
#include<bits/stdc++.h>
using namespace std;

template <int MOD_>
struct modnum {
	static constexpr int MOD = MOD_;
	static_assert(MOD_ > 0, "MOD must be positive");
 
private:
	using ll = long long;
 
	int v;
 
	static int minv(int a, int m) {
		a %= m;
		assert(a);
		return a == 1 ? 1 : int(m - ll(minv(m, a)) * ll(m) / a);
	}
 
public:
 
	modnum() : v(0) {}
	modnum(ll v_) : v(int(v_ % MOD)) { if (v < 0) v += MOD; }
	explicit operator int() const { return v; }
	friend std::ostream& operator << (std::ostream& out, const modnum& n) { return out << int(n); }
	friend std::istream& operator >> (std::istream& in, modnum& n) { ll v_; in >> v_; n = modnum(v_); return in; }
 
	friend bool operator == (const modnum& a, const modnum& b) { return a.v == b.v; }
	friend bool operator != (const modnum& a, const modnum& b) { return a.v != b.v; }
 
	modnum inv() const {
		modnum res;
		res.v = minv(v, MOD);
		return res;
	}
	modnum neg() const {
		modnum res;
		res.v = v ? MOD-v : 0;
		return res;
	}
 
	modnum operator- () const {
		return neg();
	}
	modnum operator+ () const {
		return modnum(*this);
	}
 
	modnum& operator ++ () {
		v ++;
		if (v == MOD) v = 0;
		return *this;
	}
	modnum& operator -- () {
		if (v == 0) v = MOD;
		v --;
		return *this;
	}
	modnum& operator += (const modnum& o) {
		v += o.v;
		if (v >= MOD) v -= MOD;
		return *this;
	}
	modnum& operator -= (const modnum& o) {
		v -= o.v;
		if (v < 0) v += MOD;
		return *this;
	}
	modnum& operator *= (const modnum& o) {
		v = int(ll(v) * ll(o.v) % MOD);
		return *this;
	}
	modnum& operator /= (const modnum& o) {
		return *this *= o.inv();
	}
 
	friend modnum operator ++ (modnum& a, int) { modnum r = a; ++a; return r; }
	friend modnum operator -- (modnum& a, int) { modnum r = a; --a; return r; }
	friend modnum operator + (const modnum& a, const modnum& b) { return modnum(a) += b; }
	friend modnum operator - (const modnum& a, const modnum& b) { return modnum(a) -= b; }
	friend modnum operator * (const modnum& a, const modnum& b) { return modnum(a) *= b; }
	friend modnum operator / (const modnum& a, const modnum& b) { return modnum(a) /= b; }
};
using num = modnum<int(1e9) + 7>;

num powmod(num a, int b) {
	num r = 1;
	while (b) {
		if (b & 1) {
			r *= a;
		}
		a *= a;
		b /= 2;
	}
	return r;
}

const int MAXN = 1.1e5;
int N, K;

num fact[MAXN];
num ifact[MAXN];
num choose(int n, int r) {
	return fact[n] * ifact[r] * ifact[n-r];
}

int main() {
	fact[0] = 1;
	for (int i = 1; i < MAXN; i++) {
		fact[i] = fact[i-1] * i;
	}
	ifact[MAXN-1] = fact[MAXN-1].inv();
	for (int i = MAXN-1; i >= 1; i--) {
		ifact[i-1] = ifact[i] * i;
	}

	cin >> N >> K;
	num ans = 0;
	for (int c = 0; c < K; c++) {
		num ways = choose(N+1, c) * powmod(K-c, N);
		if (c % 2 == 0) {
			ans += ways;
		} else {
			ans -= ways;
		}
	}
	cout << ans << '\n';

	return 0;
}
# Verdict Execution time Memory Grader output
1 Correct 5 ms 1400 KB Output is correct
2 Correct 5 ms 1144 KB Output is correct
3 Correct 5 ms 1144 KB Output is correct
4 Correct 4 ms 1144 KB Output is correct
5 Correct 4 ms 1144 KB Output is correct
6 Correct 4 ms 1144 KB Output is correct
7 Correct 4 ms 1144 KB Output is correct
8 Correct 4 ms 1144 KB Output is correct
9 Correct 5 ms 1144 KB Output is correct
10 Correct 4 ms 1144 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 5 ms 1400 KB Output is correct
2 Correct 5 ms 1144 KB Output is correct
3 Correct 5 ms 1144 KB Output is correct
4 Correct 4 ms 1144 KB Output is correct
5 Correct 4 ms 1144 KB Output is correct
6 Correct 4 ms 1144 KB Output is correct
7 Correct 4 ms 1144 KB Output is correct
8 Correct 4 ms 1144 KB Output is correct
9 Correct 5 ms 1144 KB Output is correct
10 Correct 4 ms 1144 KB Output is correct
11 Correct 5 ms 1144 KB Output is correct
12 Correct 5 ms 1228 KB Output is correct
13 Correct 5 ms 1144 KB Output is correct
14 Correct 4 ms 1144 KB Output is correct
15 Correct 4 ms 1144 KB Output is correct
16 Correct 4 ms 1144 KB Output is correct
17 Correct 5 ms 1144 KB Output is correct
18 Correct 4 ms 1144 KB Output is correct
19 Correct 4 ms 1144 KB Output is correct
20 Correct 4 ms 1144 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 5 ms 1400 KB Output is correct
2 Correct 5 ms 1144 KB Output is correct
3 Correct 5 ms 1144 KB Output is correct
4 Correct 4 ms 1144 KB Output is correct
5 Correct 4 ms 1144 KB Output is correct
6 Correct 4 ms 1144 KB Output is correct
7 Correct 4 ms 1144 KB Output is correct
8 Correct 4 ms 1144 KB Output is correct
9 Correct 5 ms 1144 KB Output is correct
10 Correct 4 ms 1144 KB Output is correct
11 Correct 5 ms 1144 KB Output is correct
12 Correct 5 ms 1228 KB Output is correct
13 Correct 5 ms 1144 KB Output is correct
14 Correct 4 ms 1144 KB Output is correct
15 Correct 4 ms 1144 KB Output is correct
16 Correct 4 ms 1144 KB Output is correct
17 Correct 5 ms 1144 KB Output is correct
18 Correct 4 ms 1144 KB Output is correct
19 Correct 4 ms 1144 KB Output is correct
20 Correct 4 ms 1144 KB Output is correct
21 Correct 5 ms 1144 KB Output is correct
22 Correct 4 ms 1272 KB Output is correct
23 Correct 5 ms 1144 KB Output is correct
24 Correct 4 ms 1144 KB Output is correct
25 Correct 4 ms 1212 KB Output is correct
26 Correct 5 ms 1144 KB Output is correct
27 Correct 9 ms 1144 KB Output is correct
28 Correct 4 ms 1144 KB Output is correct
29 Correct 4 ms 1144 KB Output is correct
30 Correct 4 ms 1144 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 5 ms 1400 KB Output is correct
2 Correct 5 ms 1144 KB Output is correct
3 Correct 5 ms 1144 KB Output is correct
4 Correct 4 ms 1144 KB Output is correct
5 Correct 4 ms 1144 KB Output is correct
6 Correct 4 ms 1144 KB Output is correct
7 Correct 4 ms 1144 KB Output is correct
8 Correct 4 ms 1144 KB Output is correct
9 Correct 5 ms 1144 KB Output is correct
10 Correct 4 ms 1144 KB Output is correct
11 Correct 5 ms 1144 KB Output is correct
12 Correct 5 ms 1228 KB Output is correct
13 Correct 5 ms 1144 KB Output is correct
14 Correct 4 ms 1144 KB Output is correct
15 Correct 4 ms 1144 KB Output is correct
16 Correct 4 ms 1144 KB Output is correct
17 Correct 5 ms 1144 KB Output is correct
18 Correct 4 ms 1144 KB Output is correct
19 Correct 4 ms 1144 KB Output is correct
20 Correct 4 ms 1144 KB Output is correct
21 Correct 5 ms 1144 KB Output is correct
22 Correct 4 ms 1272 KB Output is correct
23 Correct 5 ms 1144 KB Output is correct
24 Correct 4 ms 1144 KB Output is correct
25 Correct 4 ms 1212 KB Output is correct
26 Correct 5 ms 1144 KB Output is correct
27 Correct 9 ms 1144 KB Output is correct
28 Correct 4 ms 1144 KB Output is correct
29 Correct 4 ms 1144 KB Output is correct
30 Correct 4 ms 1144 KB Output is correct
31 Correct 5 ms 1144 KB Output is correct
32 Correct 4 ms 1144 KB Output is correct
33 Correct 5 ms 1144 KB Output is correct
34 Correct 6 ms 1224 KB Output is correct
35 Correct 13 ms 1144 KB Output is correct
36 Correct 14 ms 1144 KB Output is correct
37 Correct 14 ms 1144 KB Output is correct
38 Correct 5 ms 1144 KB Output is correct
39 Correct 8 ms 1144 KB Output is correct
40 Correct 8 ms 1144 KB Output is correct