Submission #1038474

#	Time	Username	Problem	Language	Result	Execution time	Memory
1038474		c2zi6	Rectangles (IOI19_rect)	C++14	100 / 100	1329 ms	468860 KiB

rect

#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
#define ff first
#define ss second
#define pb push_back
#define all(a) (a).begin(), (a).end()
#define replr(i, a, b) for (int i = int(a); i <= int(b); ++i)
#define reprl(i, a, b) for (int i = int(a); i >= int(b); --i)
#define rep(i, n) for (int i = 0; i < int(n); ++i)
#define mkp(a, b) make_pair(a, b)
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef vector<int> VI;
typedef vector<PII> VPI;
typedef vector<VI> VVI;
typedef vector<VVI> VVVI;
typedef vector<VPI> VVPI;
typedef pair<ll, ll> PLL;
typedef vector<ll> VL;
typedef vector<PLL> VPL;
typedef vector<VL> VVL;
typedef vector<VVL> VVVL;
typedef vector<VPL> VVPL;
template<class T> T setmax(T& a, T b) {if (a < b) return a = b; return a;}
template<class T> T setmin(T& a, T b) {if (a < b) return a; return a = b;}
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
template<class T>
using indset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#include "rect.h"

namespace TEST1 {
    int lg[3001];
    struct SPARSETABLE {
        VVI table;
        SPARSETABLE(){};
        SPARSETABLE(VI a) {
            int n = a.size();
            table = VVI(n, VI(14));
            reprl(i, n-1, 0) {
                table[i][0] = a[i];
                for (int j = 1; i+(1<<(j-1)) < n; j++) {
                    table[i][j] = max(table[i][j-1], table[i + (1<<(j-1))][j-1]);
                }
            }
        }
        int get(int l, int r) {
            int s = lg[r - l + 1];
            return max(table[l][s], table[r-(1<<s)+1][s]);
        }
    };
    ll count_rectangles(VVI a) {
        lg[1] = 0; replr(i, 2, 3000) lg[i] = lg[i/2]+1;
        int n = a.size();
        int m = a[0].size();
        vector<SPARSETABLE> rows(n);
        vector<SPARSETABLE> cols(m);
        rep(i, n) {
            rows[i] = SPARSETABLE(a[i]);
        }
        rep(j, m) {
            VI b;
            rep(i, n) b.pb(a[i][j]);
            cols[j] = SPARSETABLE(b);
        }
        ll ans = 0;
        replr(r1, 1, n-2) replr(r2, r1, n-2) {
            replr(c1, 1, m-2) replr(c2, c1, m-2) {
                bool good = true;
                replr(i, r1, r2) {
                    if (rows[i].get(c1, c2) >= min(a[i][c1-1], a[i][c2+1])) {
                        good = false;
                        break;
                    }
                }
                if (!good) continue;
                replr(j, c1, c2) {
                    if (cols[j].get(r1, r2) >= min(a[r1-1][j], a[r2+1][j])) {
                        good = false;
                        break;
                    }
                }
                if (!good) continue;
                /*cout << r1 << " " << r2 << " " << c1 << " " << c2 << endl;*/
                ans++;
            }
        }
        return ans;
    }
}

int gu[3000][3000], gd[3000][3000], gl[3000][3000], gr[3000][3000];
int lu[3000][3000], ru[3000][3000], ul[3000][3000], dl[3000][3000];

VL rect;
void check(int x1, int x2, int y1, int y2) {
    if (x2 < x1 || y2 < y1) return;
    /*cout << x1 << " " << x2 << " " << y1 << " " << y2 << endl;*/
    /*cout << "STATEMENTS:\n";*/
    /*cout << (gu[x2+1][y2] == x1-1 && ul[x2+1][y2] <= y1) << " || " << (gd[x1-1][y2] == x2+1 && dl[x1-1][y2] <= y1) << endl;*/
    /*cout << (gr[x2][y1-1] == y2+1 && ru[x2][y1-1] <= x1) << " || " << (gl[x2][y2+1] == y1-1 && lu[x2][y2+1] <= x1) << endl;*/
    if ((gu[x2+1][y2] == x1-1 && ul[x2+1][y2] <= y1) || (gd[x1-1][y2] == x2+1 && dl[x1-1][y2] <= y1)); else return;
    if ((gr[x2][y1-1] == y2+1 && ru[x2][y1-1] <= x1) || (gl[x2][y2+1] == y1-1 && lu[x2][y2+1] <= x1)); else return;
    rect.pb(1ll*x1*3000*3000*3000 + 1ll*x2*3000*3000 + 1ll*y1*3000 + 1ll*y2);
}

ll count_rectangles(VVI a) {
    int n = a.size();
    int m = a[0].size();
    rep(i, n) {
        stack<int> st;
        replr(j, 0, m-1) {
            while (st.size() && a[i][st.top()] < a[i][j]) st.pop();
            gl[i][j] = (st.size() ? st.top() : -1);
            st.push(j);
        }
        st = stack<int>();
        reprl(j, m-1, 0) {
            while (st.size() && a[i][st.top()] < a[i][j]) st.pop();
            gr[i][j] = (st.size() ? st.top() : -1);
            st.push(j);
        }
    }
    rep(j, m) {
        stack<int> st;
        replr(i, 0, n-1) {
            while (st.size() && a[st.top()][j] < a[i][j]) st.pop();
            gu[i][j] = (st.size() ? st.top() : -1);
            st.push(i);
        }
        st = stack<int>();
        reprl(i, n-1, 0) {
            while (st.size() && a[st.top()][j] < a[i][j]) st.pop();
            gd[i][j] = (st.size() ? st.top() : -1);
            st.push(i);
        }
    }
    rep(i, n) {
        rep(j, m) {
            if (~gl[i][j]) {
                if (i && gl[i-1][j] == gl[i][j]) lu[i][j] = lu[i-1][j];
                else if (i && gr[i-1][gl[i][j]] == j) lu[i][j] = ru[i-1][gl[i][j]];
                else lu[i][j] = i;
            }
            if (~gr[i][j]) {
                if (i && gr[i-1][j] == gr[i][j]) ru[i][j] = ru[i-1][j];
                else if (i && gl[i-1][gr[i][j]] == j) ru[i][j] = lu[i-1][gr[i][j]];
                else ru[i][j] = i;
            }
        }
    }
    rep(j, m) {
        rep(i, n) {
            if (~gu[i][j]) {
                if (j && gu[i][j-1] == gu[i][j]) ul[i][j] = ul[i][j-1];
                else if (j && gd[gu[i][j]][j-1] == i) ul[i][j] = dl[gu[i][j]][j-1];
                else ul[i][j] = j;
            }
            if (~gd[i][j]) {
                if (j && gd[i][j-1] == gd[i][j]) dl[i][j] = dl[i][j-1];
                else if (j && gu[gd[i][j]][j-1] == i) dl[i][j] = ul[gd[i][j]][j-1];
                else dl[i][j] = j;
            } else dl[i][j] = -1;
        }
    }
    rect.clear();
    replr(i, 1, n-2) replr(j, 1, m-2) {
        if (~gd[i-1][j] && ~gr[i][j-1]) check(i, gd[i-1][j]-1, j, gr[i][j-1]-1);
        if (~gd[i-1][j] && ~gl[i][j+1]) check(i, gd[i-1][j]-1, gl[i][j+1]+1, j);
        if (~gu[i+1][j] && ~gr[i][j-1]) check(gu[i+1][j]+1, i, j, gr[i][j-1]-1);
        if (~gu[i+1][j] && ~gl[i][j+1]) check(gu[i+1][j]+1, i, gl[i][j+1]+1, j);
        if (!~gr[i][j-1]) continue;
        int nextj = gr[i][j-1]-1;
        if (~gu[i+1][nextj]) check(gu[i+1][nextj]+1, i, j, nextj);
        if (~gd[i-1][nextj]) check(i, gd[i-1][nextj]-1, j, nextj);
    }
    ll ans = 0;
    if (rect.size()) {
        sort(all(rect));
        ans = 1;
        rep(i, rect.size()-1) ans += (rect[i] != rect[i+1]);
    }
    return ans;

    cout << ans << endl;
    return 0;
    if (ans == 0) return 0;
    ll real = TEST1::count_rectangles(a);
    cout << "MY ANSWER: " << ans << endl;
    cout << "REAL ANSWER: " << real << endl;
    if (real != ans) {
        rep(i, 300) cout << "ABORT ";
        cout << endl;
        rep(i, n) {
            rep(j, m) cout << a[i][j] << " ";
            cout << endl;
        }
        cout << endl;
        string _;
        while (cin >> _);
    }
    return ans;
}

• 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