Submission #297434

#	Time	Username	Problem	Language	Result	Execution time	Memory
297434		A02	Rectangles (IOI19_rect)	C++14	50 / 100	5052 ms	50552 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;

    bool all_one = true;
    for (int i = 0; i < n; i++){
        for (int j = 0; j < m; j++){
            if (a[i][j] > 1){
                all_one = false;
                break;
            }
        }
    }

    if (all_one){

        vector<vector<bool> > visited (n, vector<bool> (m, false));

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

                if (a[i][j] == 0 && !visited[i][j]){

                    vector<pair<int, int> > ones;
                    bool bad = false;

                    queue<pair<int, int> > to_visit;

                    to_visit.push(make_pair(i, j));

                    visited[i][j] = true;

                    while(!to_visit.empty()){

                        pair<int, int> current = to_visit.front();
                        to_visit.pop();

                        if (current.first == 0 || current.first == n - 1 || current.second == 0 || current.second == m - 1){
                            bad = true;
                        }

                        int ic = current.first;
                        int jc = current.second;

                        if (ic < n - 1 && !visited[ic + 1][jc]){
                            if (a[ic + 1][jc] == 1){
                                ones.push_back(make_pair(ic + 1, jc));
                            } else {
                                visited[ic + 1][jc] = true;
                                to_visit.push(make_pair(ic + 1, jc));
                            }
                        }
                        if (ic > 0 && !visited[ic - 1][jc]){
                            if (a[ic - 1][jc] == 1){
                                ones.push_back(make_pair(ic - 1, jc));
                            } else {
                                visited[ic - 1][jc] = true;
                                to_visit.push(make_pair(ic - 1, jc));
                            }
                        }
                        if (jc < m - 1 && !visited[ic][jc + 1]){
                            if (a[ic][jc + 1] == 1){
                                ones.push_back(make_pair(ic, jc + 1));
                            } else {
                                visited[ic][jc + 1] = true;
                                to_visit.push(make_pair(ic, jc + 1));
                            }
                        }
                        if (jc > 0 && !visited[ic][jc - 1]){
                            if (a[ic][jc - 1] == 1){
                                ones.push_back(make_pair(ic, jc - 1));
                            } else {
                                visited[ic][jc - 1] = true;
                                to_visit.push(make_pair(ic, jc - 1));
                            }
                        }

                    }

                    if (!bad){

                        int mini = n;
                        int maxi = 0;
                        int minj = m;
                        int maxj = 0;

                        for (int x = 0; x < ones.size(); x++){
                            mini = min(mini, ones[x].first);
                            minj = min(minj, ones[x].second);
                            maxi = max(maxi, ones[x].first);
                            maxj = max(maxj, ones[x].second);
                        }

                        for (int x = 0; x < ones.size(); x++){
                            if (ones[x].first != mini && ones[x].first != maxi && ones[x].second != minj && ones[x].second != maxj){
                                bad = true;
                                break;
                            }
                        }

                    }

                    if (!bad){
                        total++;
                    }

                }

            }
        }

        return total;

    }

    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 c1 = 1; c1 < m - 1; c1++){
        for (int r1 = 1; r1 < n - 1; r1++){
            bool b = false;
            if (b){
                break;
            }
            int right = max_right[r1][c1 - 1];
            for (int r2 = r1; r2 < n - 1; r2++){
                right = min(right, max_right[r2][c1 - 1]);

                int down = max_down[r1 - 1][c1];
                int up = min_up[r2 + 1][c1];

                for (int c2 = c1; c2 < m - 1 && c2 < right; c2++){

                    down = min(down, max_down[r1 - 1][c2]);
                    up = max(up, min_up[r2 + 1][c2]);

                    if (down > r2){
                        if (up < r1){
                                if (queryMaxSegTree(min_left_seg_trees[c2 + 1], r1, r2 + 1) < c1){
                                    total++;
                                }
                        } else{
                            //b = true;
                            break;
                        }
                    } else{
                        b = true;
                        break;
                    }
                }
            }
        }
    }

    return total;
}

Compilation message (stderr)

rect.cpp: In function 'long long int count_rectangles(std::vector<std::vector<int> >)':
rect.cpp:166:43: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  166 |                         for (int x = 0; x < ones.size(); x++){
      |                                         ~~^~~~~~~~~~~~~
rect.cpp:173:43: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  173 |                         for (int x = 0; x < ones.size(); x++){
      |                                         ~~^~~~~~~~~~~~~

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