Submission #278505

#	Time	Username	Problem	Language	Result	Execution time	Memory
278505		Kastanda	Rectangles (IOI19_rect)	C++14	10 / 100	948 ms	141608 KiB

rect

// M
#include<bits/stdc++.h>
#include "rect.h"
using namespace std;
const int N = 2505, MXN = N * N, LG = 13;
int L[N][N], R[N][N], D[N][N], U[N][N], RMQ[LG][N], Log[N];
bool Cant[MXN];
vector < int > qL[N], qR[N], qU[N], qD[N];
vector < int > Gen(vector < int > A, int w = 0)
{
        int k = (int)A.size();
        vector < int > Rs(k);
        for (int i = 0; i < k; i ++)
        {
                Rs[i] = i - 1;
                while (Rs[i] >= 0 && A[Rs[i]] < A[i] + w)
                        Rs[i] = Rs[Rs[i]];
        }
        return Rs;
}
long long count_rectangles(vector < vector < int > > A)
{
        int n = (int)A.size();
        int m = (int)A[0].size();

        for (int i = 0; i < n; i ++)
        {
                vector < int > temp, res;
                for (int j = 0; j < m; j ++)
                        temp.push_back(A[i][j]);
                res = Gen(temp, 1);
                for (int j = 0; j < m; j ++)
                        L[i][j] = res[j];
                reverse(temp.begin(), temp.end());
                res = Gen(temp, 1);
                for (int j = 0; j < m; j ++)
                        R[i][j] = m - res[m - j - 1] - 1;
        }

        for (int j = 0; j < m; j ++)
        {
                vector < int > temp, res;
                for (int i = 0; i < n; i ++)
                        temp.push_back(A[i][j]);
                res = Gen(temp, 1);
                for (int i = 0; i < n; i ++)
                        U[i][j] = res[i];
                reverse(temp.begin(), temp.end());
                res = Gen(temp, 1);
                for (int i = 0; i < n; i ++)
                        D[i][j] = n - res[n - i - 1] - 1;
        }

        vector < tuple < int , int , int , int > > Cands;
        for (int i = 0; i < n; i ++)
                for (int j = 0; j < m; j ++)
                        if (L[i][j] >= 0 && R[i][j] < m && U[i][j] >= 0 && D[i][j] < n)
                                Cands.push_back(make_tuple(U[i][j], D[i][j], L[i][j], R[i][j]));

        for (int i = 0; i < n; i ++)
        {
                vector < int > temp, res;
                for (int j = 0; j < m; j ++)
                        temp.push_back(A[i][j]);
                res = Gen(temp, 0);
                for (int j = 0; j < m; j ++)
                        L[i][j] = res[j];
                reverse(temp.begin(), temp.end());
                res = Gen(temp, 0);
                for (int j = 0; j < m; j ++)
                        R[i][j] = m - res[m - j - 1] - 1;
        }

        for (int j = 0; j < m; j ++)
        {
                vector < int > temp, res;
                for (int i = 0; i < n; i ++)
                        temp.push_back(A[i][j]);
                res = Gen(temp, 0);
                for (int i = 0; i < n; i ++)
                        U[i][j] = res[i];
                reverse(temp.begin(), temp.end());
                res = Gen(temp, 0);
                for (int i = 0; i < n; i ++)
                        D[i][j] = n - res[n - i - 1] - 1;
        }

        for (int i = 0; i < n; i ++)
                for (int j = 0; j < m; j ++)
                {
                        L[i][j] = j - L[i][j];
                        R[i][j] = R[i][j] - j;
                        U[i][j] = i - U[i][j];
                        D[i][j] = D[i][j] - i;
                }

        for (int i = 0; i < (int)Cands.size(); i ++)
        {
                int a, b, c, d;
                tie(a, b, c, d) = Cands[i];
                assert(a + 1 < b && c + 1 < d);
                qL[d].push_back(i);
                qR[c].push_back(i);
                qU[b].push_back(i);
                qD[a].push_back(i);
        }

        auto GetMin = [&](int l, int r) {
                int lg = Log[r - l];
                return min(RMQ[lg][l], RMQ[lg][r - (1 << lg)]);
        };

        for (int i = 2; i < N; i ++)
                Log[i] = Log[i >> 1] + 1;

        for (int i = 0; i < n; i ++)
        {
                for (int j = 0; j < m; j ++)
                        RMQ[0][j] = U[i][j];
                for (int lg = 1; lg < LG; lg ++)
                        for (int j = 0; j + (1 << lg) <= m; j ++)
                                RMQ[lg][j] = min(RMQ[lg - 1][j], RMQ[lg - 1][j + (1 << (lg - 1))]);
                for (int id : qU[i])
                {
                        int a, b, c, d;
                        tie(a, b, c, d) = Cands[id];
                        if (GetMin(c + 1, d) < b - a)
                                Cant[id] = 1;
                }

                for (int j = 0; j < m; j ++)
                        RMQ[0][j] = D[i][j];
                for (int lg = 1; lg < LG; lg ++)
                        for (int j = 0; j + (1 << lg) <= m; j ++)
                                RMQ[lg][j] = min(RMQ[lg - 1][j], RMQ[lg - 1][j + (1 << (lg - 1))]);
                for (int id : qD[i])
                {
                        int a, b, c, d;
                        tie(a, b, c, d) = Cands[id];
                        if (GetMin(c + 1, d) < b - a)
                                Cant[id] = 1;
                }
        }

        for (int j = 0; j < m; j ++)
        {
                for (int i = 0; i < m; i ++)
                        RMQ[0][i] = L[i][j];
                for (int lg = 1; lg < LG; lg ++)
                        for (int i = 0; i + (1 << lg) <= n; i ++)
                                RMQ[lg][i] = min(RMQ[lg - 1][i], RMQ[lg - 1][i + (1 << (lg - 1))]);
                for (int id : qL[j])
                {
                        int a, b, c, d;
                        tie(a, b, c, d) = Cands[id];
                        if (GetMin(a + 1, b) < d - c)
                                Cant[id] = 1;
                }

                for (int i = 0; i < m; i ++)
                        RMQ[0][i] = R[i][j];
                for (int lg = 1; lg < LG; lg ++)
                        for (int i = 0; i + (1 << lg) <= n; i ++)
                                RMQ[lg][i] = min(RMQ[lg - 1][i], RMQ[lg - 1][i + (1 << (lg - 1))]);
                for (int id : qR[j])
                {
                        int a, b, c, d;
                        tie(a, b, c, d) = Cands[id];
                        if (GetMin(a + 1, b) < d - c)
                                Cant[id] = 1;
                }
        }

        int Cnt = 0;
        for (int i = 0; i < (int)Cands.size(); i ++)
                if (!Cant[i])
                        Cnt ++;
        return Cnt;
}

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