Submission #745536

#	Time	Username	Problem	Language	Result	Execution time	Memory
745536		MohamedAliSaidane	Rectangles (IOI19_rect)	C++14	0 / 100	46 ms	23236 KiB

rect

#include <bits/stdc++.h>
//#include "rect.h"
using namespace std;
typedef long long ll;

typedef vector<int> vi;

#define pb push_back
#define ff first
#define ss second

const int nax = 2505;

int nx[4] = {0, 0, -1, 1};
int ny[4] = {1, -1, 0, 0};

int n, m;
vector<vi> A;
ll ans = 0ll;
int LG[nax];
int spr[nax][nax][12];
int spc[nax][nax][12];
int vis[nax][nax];
vector<pair<int,int>> comp;
int minix, miniy, maxix, maxiy;

void dfs(int x, int y)
{
    vis[x][y] = 1;
    comp.pb({x, y});
    minix = min(minix, x);
    miniy = min(miniy, y);
    maxix = max(maxix, x);
    maxiy = max(maxiy, y);
    for(int i = 0; i < 4; i++)
    {
        int nwx = nx[i] + x;
        int nwy = ny[i] + y;
        if(nwx >= 0 && nwx < n && nwy >= 0 && nwy < m)
        {
            if(vis[nwx][nwy] || A[nwx][nwy])
                continue;
            dfs(nwx, nwy);
        }
    }
}
void init()
{
    LG[1] = 0;
    for(int i = 2; i < nax; i++)
        LG[i] = LG[i/2] + 1;
    for(int row = 0; row < n; row++)
    {
        for(int col = 0; col < m; col++)
            spr[row][col][0] = spc[col][row][0] =  A[row][col];
    }
    for(int j = 1; j < 12; j++)
    {
        for(int row = 0; row < n; row++)
        {
            for(int col = 0; col < m; col++)
            {
                spr[row][col][j] = max(spr[row][col][j - 1], spr[row][col + (1 << (j - 1))][j - 1]);
                spc[col][row][j] = max(spc[col][row][j - 1], spc[col][row + (1 << (j - 1))][j - 1]);
            }
        }
    }
}
int maxir(int row, int l, int r)
{
    int j = LG[r - l + 1];
    return max(spr[row][l][j], spr[row][r - (1 << j) + 1][j]);
}
int maxic(int col, int l, int r)
{
    int j = LG[r - l + 1];
    return max(spc[col][l][j], spc[col][r - (1 << j) + 1][j]);
}
ll count_rectangles(vector<vi> a)
{
    n = a.size();
    m = a[0].size();
    A= a;
    if(n <= 2 || m <= 2)
        return 0ll;
    init();
    for(int i = 0; i < n; i++)
    {
        for(int j = 0 ; j < m; j++)
        {
            if(!vis[i][j] && (A[i][j] == 0))
            {
                minix = n, maxix = -1;
                miniy = m, maxiy = -1;
                dfs(i, j);
                int sz = comp.size();
                if(sz == (maxix- minix + 1) * (maxiy - miniy + 1))
                    ans++;
                comp.clear();
            }
        }
    }
}

Compilation message (stderr)

rect.cpp: In function 'll count_rectangles(std::vector<std::vector<int> >)':
rect.cpp:103:1: warning: control reaches end of non-void function [-Wreturn-type]
  103 | }
      | ^

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