Submission #588764

#	Time	Username	Problem	Language	Result	Execution time	Memory
588764		nguyen31hoang08minh2003	Zapina (COCI20_zapina)	C++14	110 / 110	296 ms	2208 KiB

zapina

/*
+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+
|../\..|../\..|../\..|../\..|../\..|../\..|../\..|../\..|../\..|../\..|../\..|../\..|../\..|../\..|../\..|../\..|../\..|
|\/..\/|\/..\/|\/..\/|\/..\/|\/..\/|\/..\/|\/..\/|\/..\/|\/..\/|\/..\/|\/..\/|\/..\/|\/..\/|\/..\/|\/..\/|\/..\/|\/..\/|
|/....\|/....\|/....\|/....\|/....\|/....\|/....\|/....\|/....\|/....\|/....\|/....\|/....\|/....\|/....\|/....\|/....\|
+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+
|\..../|\..../|\..../|\..../|\..../|\..../|\..../|\..../|\..../|\..../|\..../|\..../|\..../|\..../|\..../|\..../|\..../|
|/\../\|/\../\|/\../\|/\../\|/\../\|/\../\|/\../\|/\../\|/\../\|/\../\|/\../\|/\../\|/\../\|/\../\|/\../\|/\../\|/\../\|
|..\/..|..\/..|..\/..|..\/..|..\/..|..\/..|..\/..|..\/..|..\/..|..\/..|..\/..|..\/..|..\/..|..\/..|..\/..|..\/..|..\/..|
+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+------+
*/
#include <bits/stdc++.h>
#define fore(i, a, b) for (signed i = (a), i##_last = (b); i < i##_last; ++i)
#define fort(i, a, b) for (signed i = (a), i##_last = (b); i <= i##_last; ++i)
#define ford(i, a, b) for (signed i = (a), i##_last = (b); i >= i##_last; --i)
#define fi first
#define se second
#define pb push_back
#define sz(x) ((int)(x).size())
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
using namespace std;
using ll = long long;
using ld = long double;

template<class A, class B> bool maxi(A &a, const B &b) {return (a < b) ? (a = b, true):false;};
template<class A, class B> bool mini(A &a, const B &b) {return (a > b) ? (a = b, true):false;};

typedef unsigned long long ull;
typedef pair<int, int> ii;
typedef vector<ll> vi;
typedef vector<ii> vii;
typedef vector<vi> vvi;
typedef vector<vii> vvii;

int findPeriod(ll a, int m) {
    int x = 1;
    map<int, int> f;
    for (int i = 0;; ++i) {
        const auto g = f.find(x);
        if (g != f.end())
            return i - (g -> se);
        f[x] = i;
        x = (x * a) % m;
    }
}

const int maxN = 355, MOD = 1e9 + 7;

int n;

int C(int n, int k) {
    static int c[maxN][maxN];
    static bool seen[maxN][maxN];
    if (n == k)
        return 1;
    if (n < k || n <= 0)
        return 0;
    if (!seen[n][k]) {
        seen[n][k] = true;
        c[n][k] = (C(n - 1, k) + C(n - 1, k - 1)) % MOD;
    }
    return c[n][k];
}

int DP(int x, int y, bool z) {
    static int dp[maxN][maxN][2];
    static bool seen[maxN][maxN][2];
    if (x <= 0)
        return !y && z;
    if (!seen[x][y][z]) {
        seen[x][y][z] = true;
        fort(t, 0, y)
            if (t == x) {
                if (z)
                    continue;
                (dp[x][y][z] += 1LL * ((DP(x - 1, y - t, false) + DP(x - 1, y - t, true)) % MOD) * C(y, t) % MOD) %= MOD;
            } else
                (dp[x][y][z] += 1LL * DP(x - 1, y - t, z) * C(y, t) % MOD) %= MOD;
    }
    return dp[x][y][z];
}

int main() {
    int n;
    #ifdef LOCAL
        freopen("input.INP", "r", stdin);
    #endif // LOCAL
    cin.tie(0) -> sync_with_stdio(0);
    cout.tie(0);
    cin >> n;
    cout << DP(n, n, false) << '\n';
    return 0;
}

• Subtask 1: 22 / 22
• Subtask 2: 33 / 33
• Subtask 3: 55 / 55