Submission #1028814

#	Time	Username	Problem	Language	Result	Execution time	Memory
1028814		onbert	Rectangles (IOI19_rect)	C++17	72 / 100	3906 ms	1048576 KiB

rect

#include "rect.h"
#include <bits/stdc++.h>
using namespace std;
#define ll long long
struct range {
    int r, mx;
};
bool cmp0(range &a, range &b) {return a.r > b.r;}
bool cmp1(range &a, range &b) {return a.mx > b.mx;}
const int maxn = 2505, INF = 1e9;
int n, m;
vector<vector<vector<pair<int,int>>>> pos[2];
vector<vector<vector<range>>> start[2];

int fen[maxn];
void update(int id, int val) {
    while (id<maxn) {
        fen[id] += val;
        id += (id & -id);
    }
}
int qry(int id) {
    int val = 0;
    while (id >= 1) {
        val += fen[id];
        id -= (id & -id);
    }
    return val;
}

long long count_rectangles(vector<vector<int32_t>> a) {
	n = a.size(), m = a[0].size();
    pos[0].resize(m);
    for (int i=0;i<m;i++) pos[0][i].resize(m - i);
    pos[1].resize(n);
    for (int i=0;i<n;i++) pos[1][i].resize(n - i);
    start[0].resize(n); start[1].resize(n);
    for (int i=0;i<n;i++) start[0][i].resize(m), start[1][i].resize(m);
    vector<pair<int,int>> cur;
    vector<int> temp;
    set<int> s;
    for (int i=0;i<n;i++) {
        cur.clear();
        for (int j=0;j<m;j++) cur.push_back({a[i][j], j});
        sort(cur.rbegin(), cur.rend());
        s.clear(); s.insert(-1); s.insert(INF);
        temp.clear();
        for (int j=0;j<m;j++) {
            auto [val, id] = cur[j];
            if (j>0 && val!=cur[j-1].first) {
                for (int x:temp) s.insert(x);
                temp.clear();
            }
            auto it = s.upper_bound(id);
            int l = *prev(it), r = *it;
            if (l!=-1 && r!=INF) {
                l++, r--;
                if (pos[0][l][r-l].size()==0 || pos[0][l][r-l].back().first!=i) {
                    pos[0][l][r-l].push_back({i, -1});
                    start[0][i][l].push_back({r, -1});
                }
            }
            temp.push_back(id);
        }
    }

    for (int j=0;j<m;j++) {
        cur.clear();
        for (int i=0;i<n;i++) cur.push_back({a[i][j], i});
        sort(cur.rbegin(), cur.rend());
        s.clear(); s.insert(-1); s.insert(INF);
        temp.clear();
        for (int i=0;i<n;i++) {
            auto [val, id] = cur[i];
            if (i>0 && val!=cur[i-1].first) {
                for (int x:temp) s.insert(x);
                temp.clear();
            }
            auto it = s.upper_bound(id);
            int l = *prev(it), r = *it;
            if (l!=-1 && r!=INF) {
                l++, r--;
                if (pos[1][l][r-l].size()==0 || pos[1][l][r-l].back().first!=j) {
                    pos[1][l][r-l].push_back({j, -1});
                    start[1][l][j].push_back({r, -1});
                }
            }
            temp.push_back(id);
        }
    }

    for (int I=0;I<=1;I++) {
        int nn = m;
        if (I==1) nn = n;
        for (int l=0;l<nn;l++) for (int r=l;r<nn;r++) {
            sort(pos[I][l][r-l].begin(), pos[I][l][r-l].end());
            int sz = pos[I][l][r-l].size();
            for (int i=sz-1;i>=0;i--) {
                if (i==sz-1 || pos[I][l][r-l][i+1].first!=pos[I][l][r-l][i].first+1) pos[I][l][r-l][i].second = pos[I][l][r-l][i].first;
                else pos[I][l][r-l][i].second = pos[I][l][r-l][i+1].second;
            }
        }
    }
    for (int I=0;I<=1;I++) {
        for (int i=0;i<n;i++) for (int j=0;j<m;j++) {
            for (auto &[r, mx]:start[I][i][j]) {
                int x = j, y = i;
                if (I==1) x = i, y = j;
                mx = (*lower_bound(pos[I][x][r-x].begin(), pos[I][x][r-x].end(), make_pair(y, -INF))).second;
            }
        }
    }
    ll ans = 0;
    vector<int> LOG;
    for (int i=0;i<n;i++) for (int j=0;j<m;j++) {
        sort(start[0][i][j].begin(), start[0][i][j].end(), cmp0);
        sort(start[1][i][j].begin(), start[1][i][j].end(), cmp1);
        int pt = -1;
        LOG.clear();
        for (auto [r, mx]:start[0][i][j]) {
            while (pt+1 < start[1][i][j].size() && start[1][i][j][pt+1].mx >= r) {
                pt++;
                update(start[1][i][j][pt].r, 1);
                LOG.push_back(start[1][i][j][pt].r);
            }
            ans += qry(mx);
        }
        for (int x:LOG) update(x, -1);
    }
    return ans;
}

Compilation message (stderr)

rect.cpp: In function 'long long int count_rectangles(std::vector<std::vector<int> >)':
rect.cpp:121:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<range>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  121 |             while (pt+1 < start[1][i][j].size() && start[1][i][j][pt+1].mx >= r) {
      |                    ~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• 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: 0 / 28