Submission #639179

#	Time	Username	Problem	Language	Result	Execution time	Memory
639179		swagchicken	Sailing Race (CEOI12_race)	C++14	90 / 100	951 ms	4036 KiB

race

/*
 ID: swagchicken1
 PROG:
 LANG: C++11
 */
 
#include <iostream>
#include <tuple>
#include <cmath>
#include <string>
#include <cstring>
#include <vector>
#include <deque>
#include <queue>
#include <stack>
#include <map>
#include <unordered_map>
#include <set>
#include <unordered_set>
#include <algorithm>
#include <vector>
#include <fstream>
#include <iomanip>
#include <ctime>
#include <cctype>
#include <climits>
#include <chrono>
#include <numeric>
#include <functional>
 
using namespace std;
 
typedef long long ll;
typedef vector<int> vi;
typedef vector< vector <int> > vvi;
typedef pair<int, int> pii;
typedef pair < pair < int, int >, int > piii;
typedef pair < pair <int, int > , pair <int, int> > piiii;
typedef pair<ll, ll> pll;
typedef vector<bool> vb;
typedef vector<char> vc;
typedef vector<string> vs;
 
#define FOR(i,a,b) for(int i = a; i < b; i ++)
#define RFOR(i,a,b) for(int i = a-1; i >= b; i --)
#define all(a) a.begin(), a.end()
#define endl '\n';
#define sz(x) (int)(x).size()
 
#define mp make_pair
#define pb push_back
#define ff first
#define ss second
 
template <typename T>
void pr(vector<T> &v) {
    FOR(i, 0, sz(v)) cout << v[i] << " ";
    cout << endl;
}
template <typename T>
void pr(vector<vector<T> > &v) {
    FOR(i, 0, sz(v)) { pr(v[i]); }
}
template <typename T>
void re(T &x) {
    cin >> x;
}
template <typename T>
void re(vector<T> &a) {
    FOR(i, 0, sz(a)) re(a[i]);
}
template <class Arg, class... Args>
void re(Arg &first, Args &... rest) {
    re(first);
    re(rest...);
}
template <typename T>
void pr(T x) {
    cout << x << endl;
}
template <class Arg, class... Args>
void pr(const Arg &first, const Args &... rest) {
    cout << first << " ";
    pr(rest...);
    cout << endl;
}
void ps() { cout << endl; }
template<class T, class... Ts>
void ps(const T& t, const Ts&... ts) {
    cout << t; if (sizeof...(ts)) cout << " "; ps(ts...);
}
 
const ll MOD  = 1000000007;
#define inf 1e18;
#define INF INT_MAX
//#define DEBUG

long double PI = 4*atan(1);
long double eps = 1e-9;

int cw[510][510];
int cc[510][510];

vvi adj(510);
vvi radj(510);
int edge[510][510] = {};


int main() {
    //auto start = chrono::high_resolution_clock::now();
    ios_base::sync_with_stdio(0);cin.tie(0);
    //ofstream cout("output.txt");
    //ifstream cin("input.txt");
    #ifdef DEBUG
        freopen("input.txt", "r", stdin);
        freopen("output.txt", "w", stdout);
        // freopen("pieaters.in", "r", stdin);
        // freopen("pieaters.out", "w", stdout);
    #endif
    int n, K; cin >> n >> K;

    FOR(i,0,n) {
        int v = -1;
        while(cin >> v) {
            v--;
            if(v == -1) break;
          //  cout << i << " " << v << endl;
            adj[i].pb(v);
            radj[v].pb(i);
            edge[i][v] = 1;
        }
    }



    FOR(d,2,n+1) {
        FOR(i,0,n) {
            int jcw = (i + d)%n;
            int k = i + 1; if(k == n) k = 0;
            // go clockwise;

            while(k != jcw) {
                
                if(edge[i][k]) {
                    cw[i][jcw] = max(cw[i][jcw], 1 + max(cc[k][i], cw[k][jcw]));
                }
           
                k++;
                if(k == n) k = 0;
            }
        
            int jcc = (i + n - d)%n;
            k = i - 1; if(k == -1) k = n-1;
            // go clockwise from ccw
            while(k != jcc) {
                if(edge[i][k]) {
                    cc[i][jcc] = max(cc[i][jcc], 1 + max(cw[k][i], cc[k][jcc]));
                }
                k--;
                if(k == -1) k = n-1;
            } 
        }
    }

    int ans = 0;
    int idx = 0;

    // FOR(i,0,n) {FOR(j,0,n) {cout << cw[i][j] << " ";} cout << endl;}
    // cout << endl;
    // FOR(i,0,n) {FOR(j,0,n) {cout << cc[i][j] << " ";} cout << endl;}
    FOR(i,0,n) {
        FOR(j,0,n) {
            ans = max(ans, cc[i][j]);
            if(cc[i][j] == ans) {
                idx = i;
                // cout << "COUNTERCLOCKWISE " << i << " to " << j << " len " << ans << endl;
            }
        
            ans = max(ans, cw[i][j]);
            if(cw[i][j] == ans) {
                idx = i;
                // cout << "CLOCKWISE " << i << " to " << j << " len " << ans << endl;
            }
            
        }
    }
    if(K == 0) {
        cout << ans << endl;
        cout << idx + 1 << endl;
        return 0;
    }
    

    FOR(i,0,n) {
        //clockwise
        int j = i + 1;
        if(j == n) j = 0;
        vi dist(510, -1e9);
        vi vis(510);
        dist[i] = 0;
        vis[i] = 1;
        vector<pii> cross;
        while(j != i) {
            int prev = j-1;
            if(prev == -1) prev = n-1;
            for(int v : radj[j]) {
                if(vis[v]) {
                    dist[j] = max(dist[j], dist[v] + 1);
                }
            }
            if(prev != i && dist[prev] > 0) {
                for(int v : adj[prev]) {
                    cross.pb({v, prev});
                }
            }
            vis[j] = 1;
            
            if(edge[j][i]) {
                while(!cross.empty()) {
                    pii x = cross.back();
                    if(!vis[x.ff]) {
                        int temp = 2 + dist[x.ss] + max(cw[x.ff][i], cc[x.ff][j]);
                        if(temp > ans) {
                            // cout << temp << " " << j << " " << i << " " << x.ss << " " << x.ff << endl;
                            ans = temp;
                            idx = j;
                        }
                    }
                    cross.pop_back();
                }
            }
            
            j++;
            if(j == n) j -= n;
        }

        j = i - 1;
        if(j == -1) j = n-1;
        dist.assign(510, -1e9);
        vis.assign(510, 0);
        dist[i] = 0;
        vis[i] = 1;
        while(j != i) {
            int prev = j+1;
            
            if(prev == n) prev = 0;

            for(int v : radj[j]) {
                if(vis[v]) {
                    dist[j] = max(dist[j], dist[v] + 1);
                }
            }

            if(prev != i && dist[prev] > 0) {
                for(int v : adj[prev]) {
                    cross.pb({v, prev});
                }
            }   
            vis[j] = 1;

            if(edge[j][i]) {
                while(!cross.empty()) {
                    pii x = cross.back();
                    if(!vis[x.ff]) {
                        int temp = 2 + dist[x.ss] + max(cw[x.ff][j], cc[x.ff][i]);
                        if(temp > ans) {
                            // cout << temp << " " << j << " " << i << " " << x.ss << " " << dist[x.ss] << " " << x.ff << endl;
                            // cout << cw[x.ff][j] << " " << cc[x.ff][i] << endl;
                            ans = temp;
                            idx = j;
                        }
                    }
                    cross.pop_back();
                }
            }
            
            j--;
            if(j == -1) j = n-1;
        }

    }

    cout << ans << endl;
    cout << idx + 1 << endl;
    

    //auto stop = chrono::high_resolution_clock::now();
    //auto duration = chrono::duration_cast<chrono::microseconds>(stop - start);
    //cout << duration.count() << endl;
    //cin.close();
    //cout.close();
}

• Subtask 1: 90 / 100