Submission #297312

#	Time	Username	Problem	Language	Result	Execution time	Memory
297312		A02	Rectangles (IOI19_rect)	C++14	25 / 100	5080 ms	157796 KiB

rect

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

using namespace std;

void updateMinSegTree(vector<int> &segtree, int p, int a){

    int N = segtree.size() / 2;

    p += N;
    segtree[p] = a;
    p /= 2;

    while (p > 0){

        segtree[p] = min(segtree[2 * p], segtree[2 * p + 1]);
        p /= 2;

    }

}

int queryMinSegTree(vector<int> &segtree, int l, int r){

    int N = segtree.size() / 2;

    int total = 2501;

    for (l += N, r += N; l < r; l /= 2, r /= 2){

        if (l % 2 == 1){
            total = min(segtree[l++], total);
        }
        if (r % 2 == 1){
            total = min(segtree[--r], total);
        }
    }

    return total;
}

void updateMaxSegTree(vector<int> &segtree, int p, int a){

    int N = segtree.size() / 2;

    p += N;
    segtree[p] = a;
    p /= 2;

    while (p > 0){

        segtree[p] = max(segtree[2 * p], segtree[2 * p + 1]);
        p /= 2;

    }

}

int queryMaxSegTree(vector<int> &segtree, int l, int r){

    int N = segtree.size() / 2;

    int total = -1;

    for (l += N, r += N; l < r; l /= 2, r /= 2){

        if (l % 2 == 1){
            total = max(segtree[l++], total);
        }
        if (r % 2 == 1){
            total = max(segtree[--r], total);
        }
    }

    return total;
}

long long count_rectangles(vector<vector<int> > a) {

    int n = a.size();
    int m = a[0].size();
    long long total = 0;

    vector<vector<int> > min_left (vector<vector<int> > (n, vector<int> (m, 0)));
    vector<vector<int> > min_up (vector<vector<int> > (n, vector<int> (m, 0)));
    vector<vector<int> > max_right (vector<vector<int> > (n, vector<int> (m, 0)));
    vector<vector<int> > max_down (vector<vector<int> > (n, vector<int> (m, 0)));

    for (int i = 0; i < n; i++){

        vector<int> current_row = a[i];
        vector<pair<int, int> > order_to_process (m, pair<int, int>());

        for (int j = 0; j < m; j++){
            order_to_process[j].first = a[i][j];
            order_to_process[j].second = j;
        }

        sort(order_to_process.begin(), order_to_process.end());

        for (int x = 0; x < m; x++){
            int current_value = order_to_process[x].first;
            int current_index = order_to_process[x].second;
            int current_right_index = current_index + 1;
            int current_left_index = current_index - 1;

            while (current_right_index < m){

                if (a[i][current_right_index] >= current_value){
                    break;
                } else {
                    current_right_index = max_right[i][current_right_index];
                }
            }

            while (current_left_index >= 0){

                if (a[i][current_left_index] >= current_value){
                    break;
                } else {
                    current_left_index = min_left[i][current_left_index];
                }
            }

            max_right[i][current_index] = current_right_index;
            min_left[i][current_index] = current_left_index;
        }

    }

    for (int j = 0; j < m; j++){

        vector<int> current_column (n, 0);

        for (int i = 0; i < n; i++){
            current_column[i] = a[i][j];
        }

        vector<pair<int, int> > order_to_process (n, pair<int, int>());

        for (int i = 0; i < n; i++){
            order_to_process[i].first = a[i][j];
            order_to_process[i].second = i;
        }

        sort(order_to_process.begin(), order_to_process.end());

        for (int x = 0; x < n; x++){
            int current_value = order_to_process[x].first;
            int current_index = order_to_process[x].second;
            int current_down_index = current_index + 1;
            int current_up_index = current_index - 1;

            while (current_down_index < n){

                if (a[current_down_index][j] >= current_value){
                    break;
                } else {
                    current_down_index = max_down[current_down_index][j];
                }
            }

            while (current_up_index >= 0){

                if (a[current_up_index][j] >= current_value){
                    break;
                } else {
                    current_up_index = min_up[current_up_index][j];
                }
            }

            max_down[current_index][j] = current_down_index;
            min_up[current_index][j] = current_up_index;
        }

    }


    vector<vector<int> > min_left_seg_trees (vector<vector<int> > (m, vector<int> (2 * n, 0)));
    vector<vector<int> > min_up_seg_trees (vector<vector<int> > (n, vector<int> (2 * m, 0)));
    vector<vector<int> > max_right_seg_trees (vector<vector<int> > (m, vector<int> (2 * n, 0)));
    vector<vector<int> > max_down_seg_trees (vector<vector<int> > (n, vector<int> (2 * m, 0)));

    for (int i = 0; i < n; i++){
        for (int j = 0; j < m; j++){
            updateMaxSegTree(min_left_seg_trees[j], i, min_left[i][j]);
            updateMinSegTree(max_right_seg_trees[j], i, max_right[i][j]);
            updateMaxSegTree(min_up_seg_trees[i], j, min_up[i][j]);
            updateMinSegTree(max_down_seg_trees[i], j, max_down[i][j]);
        }
    }


    for (int r1 = 1; r1 < n - 1; r1++){
        for (int r2 = r1; r2 < n - 1; r2++){
            for (int c1 = 1; c1 < m - 1; c1++){
                for (int c2 = c1; c2 < m - 1; c2++){

                    int down = queryMinSegTree(max_down_seg_trees[r1 - 1], c1, c2 + 1);
                    int up = queryMaxSegTree(min_up_seg_trees[r2 + 1], c1, c2 + 1);
                    int right = queryMinSegTree(max_right_seg_trees[c1 - 1], r1, r2 + 1);
                    int left = queryMaxSegTree(min_left_seg_trees[c2 + 1], r1, r2 + 1);

                    //cout << r1 << ' ' << c1 << 'a' << r2 << ' ' << c2 << endl;
                    //cout << down << ' ' << up << ' ' << left << ' ' << right << endl;

                    if (down > r2 && up < r1 && right > c2 && left < c1){
                        //cout << r1 << ' ' << c1 << ' ' << r2 << ' ' << c2 << endl;
                        //cout << a[r1][c1] << ' ' << a[r2][c2] << endl;
                        //cout << up << endl;
                        total++;
                    }
                }
            }
        }
    }

    return total;
}

• Subtask 1: 8 / 8
• Subtask 2: 7 / 7
• Subtask 3: 0 / 12
• Subtask 4: 0 / 22
• Subtask 5: 10 / 10
• Subtask 6: 0 / 13
• Subtask 7: 0 / 28