Submission #160927

#	Time	Username	Problem	Language	Result	Execution time	Memory
160927		georgerapeanu	Rectangles (IOI19_rect)	C++14	0 / 100	19 ms	11640 KiB

rect

#include "rect.h"

#pragma once
#include <vector>
#include <algorithm>
#include <map>

using namespace std;

int aib[2505][2505];
int n,m;
void update_aib(int x,int y,int val){
    x++;
    y++;
    for(int i = x;i;i -= (-i) & i){
        for(int j = y;j;j -= (-j) & j){
            aib[i][j] += val;
        }
    }
}

int query_aib(int x,int y){
    x++;
    y++;
    int ans = 0;
    for(int i = x;i <= n;i += (-i) & i){
        for(int j = y;j <= m;j += (-j) & j){
            ans += aib[i][j];
        }
    }
    return ans;
}

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

    map<pair<int,int>,int> h_heights;
    map<pair<int,int>,int> v_heights;

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

    long long ans = 0;

    vector<vector<int> > v_stack(m,vector<int>(0));
    vector<vector<vector<int> > > tervals(n,vector<vector<int> >(m,vector<int>(0)));
    for(int i = 0;i < n;i++){
        vector<int> h_stack;
        v_heights.clear();
        for(int j = 0;j < m;j++){
            map<pair<int,int>,int> tmp;
            while(v_stack[j].size() > 0 && a[v_stack[j].back()][j] < a[i][j]){
                tmp[{v_stack[j].back(),i}] = 1 + v_heights[{v_stack[j].back(),i}];
                v_stack[j].pop_back();
            }
            if(v_stack[j].size() > 0){
                tmp[{v_stack[j].back(),i}] = 1 + v_heights[{v_stack[j].back(),i}];
            }
            v_stack[j].push_back(i);
            v_heights = tmp;
            if(i > 0 && j < m - 1){
                for(auto it:tervals[i - 1][j + 1]){
                    if(it == j){
                        continue;
                    }
                    update_aib(it,h_heights[{it,j + 1}],1);
                }

                for(auto it:v_heights){
                    if(it.first.first == it.first.second - 1){
                        continue;
                    }
                    ans += query_aib(max(0,j - it.second),it.first.second - it.first.first - 1);
                }
                
                for(auto it:tervals[i - 1][j + 1]){
                    if(it == j){
                        continue;
                    }
                    update_aib(it,h_heights[{it,j + 1}],-1);
                }
            }
        }
        map<pair<int,int>,int> tmp;
        for(int j = 0;j < m;j++){
            while(h_stack.size() > 0 && a[i][h_stack.back()] < a[i][j]){
                tmp[{h_stack.back(),j}] = 1 + h_heights[{h_stack.back(),j}];
                tervals[i][j].push_back(h_stack.back());
                h_stack.pop_back();
            }
            if(h_stack.size() > 0){
                tmp[{h_stack.back(),j}] = 1 + h_heights[{h_stack.back(),j}];
                tervals[i][j].push_back(h_stack.back());
            }
            h_stack.push_back(j);
        }
        h_heights = tmp;
    }

	return ans;
}

Compilation message (stderr)

rect.cpp:3:9: warning: #pragma once in main file
 #pragma once
         ^~~~

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