Submission #856193

# Submission time Handle Problem Language Result Execution time Memory
856193 2023-10-02T19:06:31 Z serifefedartar Zapina (COCI20_zapina) C++17
110 / 110
226 ms 2644 KB
#include <bits/stdc++.h>
using namespace std;
 
#define fast ios::sync_with_stdio(0);cin.tie(0);
#define s second
#define f first
typedef long long ll;
const ll MOD = 1e9 + 7;
const ll LOGN = 18; 
const ll INF = 1e15;
const ll MAXN = 400;

ll expo(ll a, ll b) {
	ll res = 1;
	while (b) {
		if (b & 1)
			res = (res * a) % MOD;
		a = (a * a) % MOD;
		b /= 2;
	}
	return res;
}

ll dp[MAXN][MAXN][2];
ll fact[5 * MAXN], inv[5 * MAXN];
ll nCr(ll n, ll r) {
	return ((fact[n] * inv[r]) % MOD * inv[n-r]) % MOD;
}

int main() {
	fast
	fact[0] = inv[0] = 1;
	for (ll i = 1; i < 5*MAXN; i++) {
		fact[i] = (fact[i-1] * i) % MOD;
		inv[i] = expo(fact[i], MOD - 2);
	}

	int N;
	cin >> N;

	dp[0][0][0] = 1;
	for (int i = 1; i <= N; i++) {
		for (int last = 0; last <= N; last++) {
			for (int now = last; now <= N; now++) {
				int rem = N - last;
				ll choose = nCr(rem, now - last);

				if (now - last != i)
					dp[i][now][0] = (dp[i][now][0] + (dp[i-1][last][0] * choose) % MOD) % MOD;

				if (i == now - last)
					dp[i][now][1] = (dp[i][now][1] + ((dp[i-1][last][0] + dp[i-1][last][1]) * choose) % MOD) % MOD;
				else
					dp[i][now][1] = (dp[i][now][1] + (dp[i-1][last][1] * choose) % MOD) % MOD;
			}
		}
	}
	cout << dp[N][N][1] << "\n";
}
# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 1 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 1 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 1 ms 348 KB Output is correct
7 Correct 1 ms 348 KB Output is correct
8 Correct 1 ms 348 KB Output is correct
9 Correct 1 ms 344 KB Output is correct
10 Correct 1 ms 348 KB Output is correct
11 Correct 1 ms 492 KB Output is correct
12 Correct 1 ms 348 KB Output is correct
13 Correct 1 ms 348 KB Output is correct
14 Correct 1 ms 496 KB Output is correct
15 Correct 1 ms 348 KB Output is correct
16 Correct 1 ms 348 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 348 KB Output is correct
2 Correct 1 ms 348 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 1 ms 348 KB Output is correct
7 Correct 1 ms 348 KB Output is correct
8 Correct 1 ms 348 KB Output is correct
9 Correct 1 ms 344 KB Output is correct
10 Correct 1 ms 348 KB Output is correct
11 Correct 1 ms 492 KB Output is correct
12 Correct 1 ms 348 KB Output is correct
13 Correct 1 ms 348 KB Output is correct
14 Correct 1 ms 496 KB Output is correct
15 Correct 1 ms 348 KB Output is correct
16 Correct 1 ms 348 KB Output is correct
17 Correct 110 ms 2192 KB Output is correct
18 Correct 1 ms 600 KB Output is correct
19 Correct 23 ms 1368 KB Output is correct
20 Correct 1 ms 604 KB Output is correct
21 Correct 155 ms 2152 KB Output is correct
22 Correct 17 ms 1168 KB Output is correct
23 Correct 2 ms 604 KB Output is correct
24 Correct 31 ms 1380 KB Output is correct
25 Correct 22 ms 1372 KB Output is correct
26 Correct 42 ms 1624 KB Output is correct
27 Correct 203 ms 2388 KB Output is correct
28 Correct 209 ms 2484 KB Output is correct
29 Correct 206 ms 2504 KB Output is correct
30 Correct 209 ms 2644 KB Output is correct
31 Correct 215 ms 2404 KB Output is correct
32 Correct 212 ms 2612 KB Output is correct
33 Correct 215 ms 2640 KB Output is correct
34 Correct 217 ms 2456 KB Output is correct
35 Correct 222 ms 2484 KB Output is correct
36 Correct 226 ms 2536 KB Output is correct
37 Correct 222 ms 2420 KB Output is correct