Submission #1185231

#	Time	Username	Problem	Language	Result	Execution time	Memory
1185231		Swan	Rectangles (IOI19_rect)	C++20	100 / 100	2693 ms	550328 KiB

rect

#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")

#include <iostream>
#include <vector>
#include <stack>
#include <algorithm>
#include <string>
#include <set>
#include <map>
#include <list>
#include <time.h>
#include <math.h>
#include <random>
#include <deque>
#include <queue>
#include <cassert>
#include <climits>
#include <unordered_map>
#include <unordered_set>
#include <iomanip>
#include <bitset>
#include <sstream>
#include <chrono>
#include <cstring>
#include <optional>
//#define int long long
#define INP freopen("subrev.in","r",stdin)
#define OUTP freopen("subrev.out","w",stdout)
using ld = long double;
using LD = ld;
 
using namespace std;

vector<pair<int, int> > getGoodPairs(vector<int>& v) {
    vector<pair<int, int> > res;

    stack<pair<int, int> > s;

    for (int i = 0; i < v.size(); i++) {
        while(s.size() && v[i] > s.top().first) s.pop();

        if (s.size() && abs(s.top().second - i) > 1) res.push_back({s.top().second, i});

        s.push({v[i], i});
    }

    while (s.size()) s.pop();

    for (int i = v.size() - 1; i >= 0; i--) {
        while(s.size() && v[i] > s.top().first) s.pop();

        if (s.size() && !(v[i] == s.top().first) && abs(i - s.top().second) > 1) {
            res.push_back({i, s.top().second});
        }

        s.push({v[i], i});
    }

    return res;
}

struct st {
    int r1, r2, col;

    st() {}
    st(int r1, int r2, int col) : r1(r1), r2(r2), col(col) {}

    bool operator<(const st& ot) const {
        if (make_pair(r1, r2) == make_pair(ot.r1, ot.r2)) return col < ot.col;
        else return make_pair(r1, r2) < make_pair(ot.r1, ot.r2);
    }
};

const int maxn = 2600, maxm = 2600;

vector<pair<int, int> > ans[maxn][maxm];

long long count_rectangles(vector<vector<int> > v) {
    int n = v.size();
    int m = v[0].size();

    vector<st> allPairs;
    vector<st> allPairsRows;

    for (int col = 0; col < m; col++) {
        vector<int> colVals;

        for (int i = 0; i < n; i++) colVals.push_back(v[i][col]);
        vector<pair<int, int> > pairsForCol = getGoodPairs(colVals);

        for (auto a : pairsForCol) allPairs.push_back(st(a.first, a.second, col));
    }

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

    for (int row = 0; row < n; row++) {
        vector<pair<int, int> > pairsForRow = getGoodPairs(v[row]);
        
        for (auto a : pairsForRow) allPairsRows.push_back(st(a.first, a.second, row));
    }

    sort(allPairsRows.begin(), allPairsRows.end());
    
    int cur = 0;
    int r = -1;
    int l = 0;

    while (l < allPairsRows.size()) {
        if (r < l) {
            r = l;
            cur = 1;
        }

        pair<int, int> curPair = {allPairsRows[l].r1, allPairsRows[l].r2};

        while (r + 1 < allPairsRows.size()) {
            pair<int, int> nextPair = {allPairsRows[r + 1].r1, allPairsRows[r + 1].r2};
            
            if (curPair == nextPair && allPairsRows[r + 1].col - allPairsRows[r].col == 1) {
                r++;
                cur++;
            }
            else break;
        }


        ans[allPairsRows[l].col][allPairsRows[l].r1].push_back({allPairsRows[l].r2, cur});
        l++;
        cur--;
    }

    cur = 0;
    r = -1;
    l = 0;
    long long res = 0;


    while (l < allPairs.size()) {
        if (r < l) {
            r = l;
            cur = 1;
        }

        pair<int, int> curPair = {allPairs[l].r1, allPairs[l].r2};

        while (r + 1 < allPairs.size()) {
            pair<int, int> nextPair = {allPairs[r + 1].r1, allPairs[r + 1].r2};
            
            if (curPair == nextPair && allPairs[r + 1].col - allPairs[r].col == 1) {
                r++;
                cur++;
            }
            else break;
        }



        if (allPairs[l].col == 0 || allPairs[l].col == m - 1 || allPairs[l].r2 - allPairs[l].r1 <= 1) {
            l++;
            cur--;
            continue; 
        }
    
       
        for (auto a : ans[allPairs[l].r1 + 1][allPairs[l].col - 1]) {
           // cout << "W " << allPairs[l].r1 << ' ' << allPairs[l].r2 << ' ' << allPairs[l].col << endl;
            if (a.first <= allPairs[r].col + 1 && allPairs[l].r2 - allPairs[l].r1 - 1 <= a.second) res++;
        }

        l++;
        cur--;
    }

    return res;
}

/*
void solve() {
    int n, m; cin >> n >> m;

    vector<vector<int> > v;

    for (int i = 0; i < n; i++) {
        vector<int> r;
        for (int j = 0; j < m; j++) {
            int x; cin >> x;
            r.push_back(x);
        }
        v.push_back(r);
    }
    cout << count_rectangles(v);
}


int main() {
    ios_base::sync_with_stdio(0);
    solve();
}



*/

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