Submission #1075946

#	Time	Username	Problem	Language	Result	Execution time	Memory
1075946		shmax	Art Class (IOI13_artclass)	C++17	62 / 100	60 ms	6368 KiB

artclass

#include "artclass.h"
#include <bits/stdc++.h>

using namespace std;

template<typename T>
using vec = vector<T>;

typedef struct {
    int r, g, b;
} RGB;

double ColourDistance(RGB e1, RGB e2) {
    long rmean = ((long) e1.r + (long) e2.r) / 2;
    long r = (long) e1.r - (long) e2.r;
    long g = (long) e1.g - (long) e2.g;
    long b = (long) e1.b - (long) e2.b;
    return sqrt((((512 + rmean) * r * r) >> 8) + 4 * g * g + (((767 - rmean) * b * b) >> 8));
}

int style(int N, int M, int R[500][500], int G[500][500], int B[500][500]) {
    map<tuple<int, int, int>, int> colors;
    vec<vec<tuple<int, int, int>>> mtr(N, vec<tuple<int, int, int>>(M));
    for (int i = 0; i < N; i++) {
        for (int j = 0; j < M; j++) {
//            colors.insert(fix_color(R[i][j], G[i][j], B[i][j]));
            mtr[i][j] = tuple<int, int, int>(R[i][j], G[i][j], B[i][j]);
        }
    }

    vec<vec<bool>> used(N, vec<bool>(M, false));
    int cnt = 0;
    int most_common = 0;
    mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());

    auto similar = [&](tuple<int, int, int> a, tuple<int, int, int> b) {
        int r1, g1, b1, r2, g2, b2;
        tie(r1, g1, b1) = a;
        tie(r2, g2, b2) = b;
        return ColourDistance({r1, g1, b1}, {r2, g2, b2}) < 200;
    };

    auto BFS = [&](int i, int j) {
        if (used[i][j]) return;
        cnt++;
        int sz = 1;
        queue<pair<int, int>> q;
        q.push({i, j});
        used[i][j] = true;
        while (!q.empty()) {
            auto [x, y] = q.front();
            q.pop();
            sz++;
            for (int dx = -1; dx <= 1; dx++) {
                for (int dy = -1; dy <= 1; dy++) {
                    if (dx == 0 && dy == 0) continue;
                    int nx = x + dx;
                    int ny = y + dy;
                    if (nx < 0 || nx >= N || ny < 0 || ny >= M) continue;
                    if (used[nx][ny]) continue;
                    if (!similar(mtr[i][j], mtr[nx][ny])) continue;
                    used[nx][ny] = true;
                    q.push({nx, ny});
                }
            }
        }
        most_common = max(most_common, sz);
    };
    for (int i = 0; i < N; i++) {
        for (int j = 0; j < M; j++) {
            BFS(i, j);
        }
    }


//    cout << most_common << " " << cnt << endl;
    if (cnt > 2200) return 3;
    if (cnt < 380) return 4;
    if (most_common < 111036) return 1;

    return 2;
//    if (cnt < 3900) {
//        return 4;
//    }
//    if (cnt < 4200) {
//        if (rnd() % 2 == 0) return 1;
//        else return 4;
//    } else {
//        if (rnd() % 2 == 0) return 2;
//        else return 3;
//    }
//    set<int> s;
//    int n = 8;
//    mt19937 rnd(228);
//    map<tuple<int, int, int>, int> rnd_m;
//    for (int i = 0; i < N - n; i++) {
//        for (int j = 0; j < M - n; j++) {
//            set<tuple<int, int, int>> cur;
//            for (int k = 0; k < n; k++) {
//                for (int l = 0; l < n; l++) {
//                    cur.insert(mtr[i + k][j + l]);
//                }
//            }
//            int hash = 0;
//            for (auto &color: cur) {
//                if (rnd_m.find(color) == rnd_m.end()) {
//                    rnd_m[color] = rnd();
//                }
//                hash = hash * 228 + rnd_m[color];
//            }
//
//            s.insert(hash);
//        }
//    }
//
//    int most_common = 0;

//    cout << colors.
//
//            size()
//
//         << " " << most_common << " " << s.
//
//            size()
//
//         <<
//         endl;

}

• Subtask 1: 62 / 100