Cod C++

#include <iostream>
#include <vector>
#define N 10001

using namespace std;

struct point
{
    int x, y;
};

struct window
{
    point A, B, C, D;
};

int n;
window w[N];

vector <int> G[N];
int closings;
bool closed[N];

inline bool inwindow( point X, window Y ) /// punctul X este in interiorul dreptunghiului Y
{
    return X.x >= Y.A.x && X.x <= Y.B.x && X.y >= Y.A.y && X.y <= Y.D.y;
}

bool intersect( window X, window Y )
{
    /// X are macar un colt in Y

    if ( inwindow( X.A, Y ) || inwindow( X.B, Y ) || inwindow( X.C, Y ) || inwindow( X.D, Y ) )
        return 1;

    /// Y are macar un colt in X

    if ( inwindow( Y.A, X ) || inwindow( Y.B, X ) || inwindow( Y.C, X ) || inwindow( Y.D, X ) )
        return 1;

    return 0;
}

void close( int node ) /// programul simuleaza recursiv inchiderea ferestrelor
{
    int i;

    for ( i = 0; i < G[node].size(); ++i ) /// parcurgem toti vecinii ferestrei node
        if ( !closed[G[node][i]] ) /// daca nu am inchis inca fereastra G[node][i]
            close(G[node][i]); /// continuam prin a-i parcurge vecinii

    closed[node] = 1; /// dupa ce am parcurs toti vecinii putem inchide fereastra node
    ++closings; /// incrementam numarul de ferestre inchise
}

void Do()
{
    int i, j;

    cin >> n;

    for ( i = 1; i <= n; ++i )
    {
        cin >> w[i].A.x >> w[i].A.y >> w[i].C.x >> w[i].C.y;

        /// generam si celelalte 2 colturi ale ferestrei

        w[i].B.x = w[i].C.x; w[i].B.y = w[i].A.y;
        w[i].D.x = w[i].A.x; w[i].D.y = w[i].C.y;

        for ( j = i - 1; j >= 1; --j )
            if ( intersect( w[j], w[i] ) ) /// daca 2 ferestre se intersecteaza
                G[j].push_back(i);         /// adaugam adiacenta in graf
    }

    close(1); /// apelam inchiderea primei ferestre

    cout << closings; /// afisam numarul minim de ferestre inchise
}

int main()
{
    Do();

    return 0;
}