Submission #223378

#	Time	Username	Problem	Language	Result	Execution time	Memory
223378		MrDomino	Rectangles (IOI19_rect)	C++14	23 / 100	771 ms	189520 KiB

rect

#include <bits/stdc++.h>
#include "rect.h"

using namespace std;

const int N = 2500 + 7;
int n;
int m;
int a[N][N];
int st[N][N];
int dr[N][N];
int sus[N][N];
int jos[N][N];
int stk[N];
int top;

bool good(int r, int c)
{
    return (1 < r && 1 < c && r < n && c < m);
}

struct T
{
    int a;
    int b;
    int c;
    int d;
};

bool operator < (T f, T s)
{
    if (f.a != s.a) return f.a < s.a;
    if (f.b != s.b) return f.b < s.b;
    if (f.c != s.c) return f.c < s.c;
    return f.d < s.d;
}

bool operator != (T f, T s)
{
    if (f.a != s.a) return 1;
    if (f.b != s.b) return 1;
    if (f.c != s.c) return 1;
    if (f.d != s.d) return 1;
    return 0;
}

vector<T> solutions;

void check(int r1, int c1, int r2, int c2)
{
    if (!good(r1, c1) || !good(r2, c2))
    {
        return;
    }
    if (r1 > r2 || c1 > c2)
    {
        return;
    }
    for (int r = r1; r <= r2; r++)
    {
        if (dr[r][c1] != c2 && st[r][c2] != c1)
        {
            return;
        }
    }
    for (int c = c1; c <= c2; c++)
    {
        if (jos[r1][c] != r2 && sus[r2][c] != r1)
        {
            return;
        }
    }
   /// cout << " : " << r1 - 1 << " " << r2 - 1 << " " << c1 - 1 << " " << c2 - 1 << "\n";
    solutions.push_back({r1, c1, r2, c2});
}

long long count_rectangles(vector<vector<int>> b)
{
    n = (int) b.size();
    m = (int) b[0].size();
    for (int i = 1; i <= n; i++)
    {
        for (int j = 1; j <= m; j++)
        {
            a[i][j] = b[i - 1][j - 1];
        }
    }
    for (int i = 1; i <= n; i++)
    {
        top = 0;
        stk[0] = 0;
        for (int j = 1; j <= m; j++)
        {
            while (top && a[i][stk[top]] < a[i][j])
            {
                top--;
            }
            st[i][j - 1] = stk[top] + 1;
            stk[++top] = j;
        }
        top = 0;
        stk[0] = m + 1;
        for (int j = m; j >= 1; j--)
        {
            while (top && a[i][stk[top]] < a[i][j])
            {
                top--;
            }
            dr[i][j + 1] = stk[top] - 1;
            stk[++top] = j;
        }
    }
    for (int j = 1; j <= m; j++)
    {
        top = 0;
        stk[0] = 0;
        for (int i = 1; i <= n; i++)
        {
            while (top && a[stk[top]][j] < a[i][j])
            {
                top--;
            }
            sus[i - 1][j] = stk[top] + 1;
            stk[++top] = i;
        }
        top = 0;
        stk[0] = n + 1;
        for (int i = n; i >= 1; i--)
        {
            while (top && a[stk[top]][j] < a[i][j])
            {
                top--;
            }
            jos[i + 1][j] = stk[top] - 1;
            stk[++top] = i;
        }
    }

    for (int i = 1; i <= n; i++)
    {
        for (int j = 1; j <= m; j++)
        {
            check(sus[i][j], st[i][j], i, j);
            check(sus[i][j], j, i, dr[i][j]);
            check(i, st[i][j], jos[i][j], j);
            check(i, j, jos[i][j], dr[i][j]);
        }
    }
    if (solutions.empty())
    {
        return 0;
    }
    sort(solutions.begin(), solutions.end());
    int sol = 1;
    for (int i = 1; i < (int) solutions.size(); i++)
    {
        sol += (solutions[i] != solutions[i - 1]);
    }
    return sol;
}

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