Submission #296608

#	Time	Username	Problem	Language	Result	Execution time	Memory
296608		Osama_Alkhodairy	Rectangles (IOI19_rect)	C++17	72 / 100	5053 ms	430164 KiB

rect

#include <bits/stdc++.h>
#include "rect.h"
//~ #include "grader.cpp"
using namespace std;
#define ll long long

const int N = 2501;
const int INF = (int)1e9;

int n, m;
vector <vector <int> > a;
set <pair <pair <int, int>, pair <int, int> > > vis;
vector <vector <int> > us, rs, ds, ls, ue, re, de, le;

vector <int> calc(vector <int> &a, int b, int c){
    //~ b = 0 for >
    //~ b = 1 for >=
    //~ c = 0 for forward
    //~ c = 1 for backward
    int n = a.size();
    vector <int> inds;
    for(int i = 0 ; i < n ; i++){
        if(c == 0) inds.push_back(i);
        else inds.push_back(n - i - 1);
    }
    vector <int> ret(n);
    vector <int> cur;
    for(auto &i : inds){
        while(cur.size() && a[i] >= a[cur.back()] + b){
            cur.pop_back();
        }
        if(cur.size() == 0) ret[i] = -1;
        else ret[i] = cur.back();
        cur.push_back(i);
    }
    return ret;
}
bool check(int r1, int c1, int r2, int c2){
    if(r1 == -1 || c1 == -1 || r2 == -1 || c2 == -1) return 0;
    if(vis.count(make_pair(make_pair(r1, c1), make_pair(r2, c2)))) return 0;
    vis.insert(make_pair(make_pair(r1, c1), make_pair(r2, c2)));
    int v = INF;
    for(int c = c1 + 1 ; c < c2 ; c++){
        if(de[r1][c] != -1) v = min(v, de[r1][c]);
    }
    if(v < r2) return 0;
    v = -INF;
    for(int c = c1 + 1 ; c < c2 ; c++){
        if(ue[r2][c] != -1) v = max(v, ue[r2][c]);
    }
    if(v > r1) return 0;
    v = INF;
    for(int r = r1 + 1 ; r < r2 ; r++){
        if(re[r][c1] != -1) v = min(v, re[r][c1]);
    }
    if(v < c2) return 0;
    v = -INF;
    for(int r = r1 + 1 ; r < r2 ; r++){
        if(le[r][c2] != -1) v = max(v, le[r][c2]);
    }
    if(v > c1) return 0;
    return 1;
}
long long count_rectangles(std::vector<std::vector<int> > A) {
    a = A;
    n = a.size();
    m = a[0].size();
    us.resize(n, vector <int>(m));
    ue.resize(n, vector <int>(m));
    ds.resize(n, vector <int>(m));
    de.resize(n, vector <int>(m));
    ls.resize(n, vector <int>(m));
    le.resize(n, vector <int>(m));
    rs.resize(n, vector <int>(m));
    re.resize(n, vector <int>(m));
    for(int i = 0 ; i < n ; i++){
        vector <int> cur = a[i];
        ls[i] = calc(cur, 0, 0);
        le[i] = calc(cur, 1, 0);
        rs[i] = calc(cur, 0, 1);
        re[i] = calc(cur, 1, 1);
    }
    for(int j = 0 ; j < m ; j++){
        vector <int> cur(n);
        for(int i = 0 ; i < n ; i++){
            cur[i] = a[i][j];
        }
        vector <int> g;
        g = calc(cur, 0, 0);
        for(int i = 0 ; i < n ; i++){
            us[i][j] = g[i];
        }
        g = calc(cur, 1, 0);
        for(int i = 0 ; i < n ; i++){
            ue[i][j] = g[i];
        }
        g = calc(cur, 0, 1);
        for(int i = 0 ; i < n ; i++){
            ds[i][j] = g[i];
        }
        g = calc(cur, 1, 1);
        for(int i = 0 ; i < n ; i++){
            de[i][j] = g[i];
        }
    }
    int ret = 0;
    for(int i = 0 ; i < n ; i++){
        for(int j = 0 ; j < m ; j++){
            ret += check(us[i][j], ls[i][j], ds[i][j], rs[i][j]);
        }
    }
    return ret;
}

• 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