Submission #95450

#	Time	Username	Problem	Language	Result	Execution time	Memory
95450		forestryks	Sailing Race (CEOI12_race)	C++14	100 / 100	1923 ms	4772 KiB

race

///////////////////////////////////////////////////////////////////////////////////////////////
#include <bits/stdc++.h>
using namespace std;

#define mp make_pair
#define pb push_back
#define FAST_IO ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)
#define FILE_IO(x) freopen((string(x) + ".in").c_str(), "r", stdin); freopen((string(x) + ".out").c_str(), "w", stdout)
#define f first
#define s second
#define x1 x1qwer
#define y1 y1qwer
#define right right123
#define left left123
#define foreach(it, v) for (auto it : v)
#define rep(it, n) for (int it = 0; it < n; ++it)
#define forin(it, l, r) for (int it = l; it < r; ++it)
#define all(x) x.begin(), x.end()

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
const double DINF = numeric_limits<double>::infinity();
const ll MOD = 1e9 + 7;
const double EPS = 1e-7;
ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
mt19937 mmtw_(MOD);
uniform_int_distribution<ll> rd_;
ll randomll() { return rd_(mmtw_);}
ll rnd(ll x, ll y) { return rd_(mmtw_) % (y - x + 1) + x; }
////////////////////////////////////////////////////////////////////////////////////////////////

const int MAXN = 505;
int n, k;
bool g[MAXN][MAXN];
int dp[MAXN][MAXN];
int dpc[MAXN][MAXN];
int ds[MAXN][MAXN];
int dsc[MAXN][MAXN];

inline int md(int x) {
    if (x >= n) return x - n;
    if (x < 0) return x + n;
    return x;
}

int f(int, int);
int fc(int, int);

int f(int a, int b) {
    if (dp[a][b] != -1) return dp[a][b];

    dp[a][b] = 0;
    for (int i = md(b + 1); i != a; i = md(i + 1)) {
        if (g[b][i]) dp[a][b] = max(dp[a][b], max(fc(b, i), f(a, i)) + 1);
    }

    return dp[a][b];
}

int fc(int a, int b) {
    if (dpc[a][b] != -1) return dpc[a][b];

    dpc[a][b] = 0;
    for (int i = md(b - 1); i != a; i = md(i - 1)) {
        if (g[b][i]) dpc[a][b] = max(dpc[a][b], max(f(b, i), fc(a, i)) + 1);
    }

    return dpc[a][b];
}

int s(int a, int b) {
    if (ds[a][b] != -2) return ds[a][b];

    ds[a][b] = -1;
    if (a == b) ds[a][b] = 0;
    if (g[a][b]) ds[a][b] = 1;
    for (int i = md(a + 1); i != b; i = md(i + 1)) {
        int ai = s(a, i);
        int ib = s(i, b);
        if (ai == -1 || ib == -1) continue;
        ds[a][b] = max(ds[a][b], ai + ib);
    }

    return ds[a][b];
}

int sc(int a, int b) {
    if (dsc[a][b] != -2) return dsc[a][b];

    dsc[a][b] = -1;
    if (a == b) dsc[a][b] = 0;
    if (g[a][b]) dsc[a][b] = 1;
    for (int i = md(a - 1); i != b; i = md(i - 1)) {
        int ai = sc(a, i);
        int ib = sc(i, b);
        if (ai == -1 || ib == -1) continue;
        dsc[a][b] = max(dsc[a][b], ai + ib);
    }

    return dsc[a][b];
}

int main() {
    FAST_IO;
    cin >> n >> k;
    rep(i, n) {
        while (true) {
            int x;
            cin >> x;
            x--;
            if (x == -1) break;
            g[i][x] = true;
        }
    }

    rep(i, n) {
        rep(j, n) {
            dp[i][j] = dpc[i][j] = -1;
            ds[i][j] = dsc[i][j] = -2;
        }
    }

    int res = 0;
    int st = 0;
    rep(i, n) {
        rep(j, n) {
            if (i == j) continue;
            if (g[i][j]) {
                int nw = max(f(i, j), fc(i, j)) + 1;
                if (nw > res) {
                    res = nw;
                    st = i;
                }
            }
        }
    }

    if (k == 1) {
        rep(b, n) {
            rep(c, n) {
                if (b == c) continue;
                if (s(b, c) == -1) continue;

                int a;
                for (a = md(c + 1); a != b; a = md(a + 1)) {
                    if (g[a][b]) break;
                }

                if (a == b) continue;

                for (int d = md(a + 1); d != b; d = md(d + 1)) {
                    if (!g[c][d]) continue;
                    int nw = 2 + s(b, c) + max(f(b, d), fc(a, d));
                    if (nw > res) {
                        res = nw;
                        st = a;
                    }
                }
            }
        }

        rep(b, n) {
            rep(c, n) {
                if (b == c) continue;
                if (sc(b, c) == -1) continue;

                int a;
                for (a = md(c - 1); a != b; a = md(a - 1)) {
                    if (g[a][b]) break;
                }

                if (a == b) continue;

                for (int d = md(a - 1); d != b; d = md(d - 1)) {
                    if (!g[c][d]) continue;
                    int nw = 2 + sc(b, c) + max(fc(b, d), f(a, d));
                    if (nw > res) {
                        res = nw;
                        st = a;
                    }
                }
            }
        }
    }

    cout << res << endl;
    cout << st + 1 << endl;
}

• Subtask 1: 100 / 100