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#include <cstdio>
#include <algorithm>
using namespace std;

struct Rectangle
{
    int x1, x2, y1, y2;
    
    void load()
    {
        scanf ("%d%d%d%d", &x1, &x2, &y1, &y2);
    }
    
    void print()
    {
        printf("%d %d %d %d\n", x1, x2, y1, y2);
    }
    
    bool operator< (const Rectangle &other) const
    {
        if (x1 == other.x1)
        {
            if (x2 == other.x2)
            {
                if (y1 == other.y1)
                    return y2 < other.y2;
                    
                return y1 < other.y1;
            }
            
            return x2 < other.x2;
        }
        
        return x1 < other.x1;
    }

    void absorb(const Rectangle &A)
    {
        if (x1 > A.x1)
            x1 = A.x1;
        
        if (y1 > A.y1)
            y1 = A.y1;
        
        if (x2 < A.x2)
            x2 = A.x2;
        
        if (y2 < A.y2)
            y2 = A.y2;
    }
};
      
bool overlaps(const Rectangle &A, const Rectangle &B)
{
    return ((B.x2 > A.x1) and (B.x1 < A.x2) and (B.y2 > A.y1) and (B.y1 < A.y2));
}

Rectangle T[100000];

int main()
{
    int n;
    
    scanf ("%d", &n);
    
    for (int i=0; i<n; i++)
        T[i].load();
    
    int prevRes = -1;
    
    while (prevRes != n)
    {
        prevRes = n;
        
        for (int i=0; i<n; i++)
        {
            for (int j=0; j<n; j++)
            {
                if (i == j)
                    continue;
                
                if (overlaps(T[i], T[j]))
                {                    
                    T[i].absorb(T[j]);
                    
                    swap(T[j], T[n-1]);
                    
                    n--, j--;
                }
                
                if (i >= n)
                    i = j + 1;
            }
        }
    }
    
    sort(T, T + n);
    
    printf("%d\n", n);
    
    for (int i=0; i<n; i++)
        T[i].print();
    
    return 0;
}