Submission #1095489

#	Time	Username	Problem	Language	Result	Execution time	Memory
1095489		hqminhuwu	Sailing Race (CEOI12_race)	C++14	90 / 100	839 ms	18432 KiB

race

#include "bits/stdc++.h"
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair <ll,ll> pll;
typedef pair <int,int> pii;
typedef pair <int,pii> piii;

#define forr(_a,_b,_c) for(int _a = (_b); _a <= int (_c); ++_a)
#define ford(_a,_b,_c) for(int _a = (_b) + 1; _a --> int (_c);)
#define forf(_a,_b,_c) for(int _a = (_b); _a < int (_c); ++_a)
#define st first
#define nd second
#define pb push_back
#define mp make_pair
#define all(x) begin(x),end(x)
#define mask(i) (1LL << (i))
#define bit(x, i) (((x) >> (i)) & 1)
#define bp __builtin_popcountll
#define file "test"

template<class X, class Y>
    bool minz(X &x, const Y &y) {
        if (x > y) {
            x = y;
            return true;
        } return false;
    }
template<class X, class Y>
    bool maxz(X &x, const Y &y) {
        if (x < y) {
            x = y;
            return true;
        } return false;
    }

const int N = 1e3 + 5;
const ll oo = (ll) 1e16;
const ll mod = 1e9 + 7; // 998244353;

int debug = 0;

int dp[N][N][2], n, t, u, uwu, f[N][N], g[N][N];
vector <int> a[N], ra[N];

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0);
    #ifdef hqm
        freopen(file".inp", "r", stdin); freopen(file".out", "w", stdout);
    #endif

    cin >> n >> uwu;

    forr (i, 1, n){
        while (cin >> u && u != 0){
            a[u].pb(i);
            a[u + n].pb(i);
            a[u].pb(i + n);
            a[u + n].pb(i + n);
            ra[i].pb(u);
            ra[i + n].pb(u);
            ra[i].pb(u + n);
            ra[i + n].pb(u + n);
        }
    }

    memset (dp, -1, sizeof dp);

    forr (i, 1, 2 * n){
        dp[i][i][0] = 0;
        dp[i][i][1] = 0;
        for (int u : a[i]){
            if (u < i)
                dp[u][i][0] = 1;
            else dp[i][u][1] = 1;
        }
    }

    int mx = 0, pos = 0;

    forr (len, 1, n){
        forr (i, 1, 2 * n - len + 1){
            int u = i, v = i + len - 1;

            forr (t, 0, 1){
                int e = (t ? v : u);

                if (dp[u][v][t] > mx){
                    mx = dp[u][v][t];
                    pos = e - n * (e > n);
                } 

                if (dp[u][v][t] != -1){
                    for (int w : a[e]){
                        if (w < u){
                            maxz(dp[w][v][0], dp[u][v][t] + 1);
                        } else if (w > v){
                            maxz(dp[u][w][1], dp[u][v][t] + 1);
                        }
                    }
                }
            }
        }
    }   

    if (uwu){
        forr (i, 1, 2 * n){
            ford (j, i, 1){
                g[i][j] = max (g[i][j + 1], dp[j][i][1]);
            }
            forr (j, i + 1, 2 * n)
                g[i][j] = max (g[i][j - 1], dp[i][j][0]);
        }

        forr (i, 1, 2 * n){
            forr (j, i, 2 * n){
                for (int u : a[j])
                if (u >= i && u < j){
                    maxz(f[i][j], f[i][u] + 1);
                }
            }

            ford (j, i, 1){
                for (int u : a[j])
                if (u <= i && u > j){
                    maxz(f[i][j], f[i][u] + 1);
                }
            }
        }

        forr (i, 1, 2 * n){
            int k = 0;
            if (a[i].empty()) continue;
            forr (j, i, 2 * n)
            if (f[i][j]){
              //  cout << i << " " << j << " " << f[i][j] << " " << a[i][k] << " " << k << " " << a[i].size() << "\n";;
                while (k < a[i].size() && a[i][k] <= j) k++;
                if (k >= a[i].size() || a[i][k] <= j) break;
                for (int u : ra[j]){
                    if (u < i && a[i][k] - u + 1 <= n){
                       // cout << i << " " << j << " " << a[i][k] << " " << u << " " << f[i][j] << " " << g[u][i - 1] << "\n";
                        if (maxz(mx, f[i][j] + g[u][i - 1] + 2))
                            pos = a[i][k];
                    }
                    if (u > a[i][k] && u - i + 1 <= n){
                    //    cout << i << " " << j << " " << a[i][k] << " " << u << " " << f[i][j] << " " << g[u][a[i][k]] << "\n";
                        if (maxz(mx, f[i][j] + g[u][a[i][k] + 1] + 2))
                        pos = a[i][k];
                    }
                }
            }   
        }

        forr (i, 1, 2 * n){
            if (a[i].empty()) continue;
            int k = a[i].size() - 1;
            ford (j, i, 1)
            if (f[i][j]){
              //  cout << i << " " << j << " " << f[i][j] << " " << a[i][k] << " " << k << " " << a[i].size() << "\n";;
                while (k >= 0 && a[i][k] >= j) k--;
                if (k < 0 || a[i][k] >= j) break;
                for (int u : ra[j]){
                    if (u < a[i][k] && i - u + 1 <= n){
                       // cout << i << " " << j << " " << a[i][k] << " " << u << " " << f[i][j] << " " << g[u][a[i][k] - 1] << "\n";
                        if (maxz(mx, f[i][j] + g[u][a[i][k] - 1] + 2))
                            pos = a[i][k];
                    }
                    if (u > i && u - a[i][k] + 1 <= n){
                        //cout << i << " " << j << " " << a[i][k] << " " << u << " " << f[i][j] << " " << g[u][i + 1] << "\n";
                        if (maxz(mx, f[i][j] + g[u][i + 1] + 2))
                            pos = a[i][k];
                    }
                }
            }   
        }
    }


    cout << mx << " " << pos - n * (pos > n) << "\n";

    return 0;
}
/*



*/

Compilation message (stderr)

race.cpp: In function 'int main()':
race.cpp:137:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  137 |                 while (k < a[i].size() && a[i][k] <= j) k++;
      |                        ~~^~~~~~~~~~~~~
race.cpp:138:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  138 |                 if (k >= a[i].size() || a[i][k] <= j) break;
      |                     ~~^~~~~~~~~~~~~~

• Subtask 1: 90 / 100