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#include <iostream>
#include <cctype>
#include <vector>
#include <algorithm>
#include <random>

#define SIZE_OF_ARRAY(x) (sizeof(x) / sizeof(*(x)))

typedef unsigned int uint;

uint get_uint()
{
	int c;
	while (isspace(c = std::cin.get()));

	uint value = (c - '0');

	while (isdigit(c = std::cin.get()))
	{
		value = (10 * value) + (c - '0');
	}

	return value;
}

static char put_uint_buffer[16];

void put_uint(uint value)
{
	if (value == 0)
	{
		std::cout.put('0');

		return;
	}

	int i;
	for (i = SIZE_OF_ARRAY(put_uint_buffer); value != 0; value /= 10)
	{
		put_uint_buffer[--i] = '0' + (value % 10);
	}

	std::cout.write(put_uint_buffer + i, SIZE_OF_ARRAY(put_uint_buffer) - i);
}

struct data
{
	int x1;
	int x2;

	int y1;
	int y2;

	bool done;
} ple[100001];

inline bool operator<(const data &a, const data &b)
{
	if (a.x1 != b.x1) return a.x1 < b.x1;
	if (a.x2 != b.x2) return a.x2 < b.x2;
	if (a.y1 != b.y1) return a.y1 < b.y1;
	                  return a.y2 < b.y2;
}

int main()
{
	std::ios_base::sync_with_stdio(false);
	std::cin.tie(0);

	uint n = get_uint();

	for (uint i = 0; i < n; ++i)
	{
		ple[i].x1 = get_uint();
		ple[i].x2 = get_uint();

		ple[i].y1 = get_uint();
		ple[i].y2 = get_uint();

		ple[i].done = false;
	}

	std::mt19937 rng(0x12345432);

	bool done = false;

	while (!done)
	{
		std::shuffle(ple, ple + n, rng);

		done = true;

		for (uint i = 0; i < n; ++i)
		{
			if (ple[i].done)
			{
				continue;
			}

			std::swap(ple[0], ple[i]);

			data &ple_i = ple[0];

			bool updated_i = false;

			for (uint j = 1; j < n; ++j)
			{
				const data &ple_j = ple[j];

				if (ple_i.x2 <= ple_j.x1 || ple_j.x2 <= ple_i.x1 || ple_i.y2 <= ple_j.y1 || ple_j.y2 <= ple_i.y1)
				{
					continue;
				}

				ple_i.x1 = std::min(ple_i.x1, ple_j.x1);
				ple_i.x2 = std::max(ple_i.x2, ple_j.x2);

				ple_i.y1 = std::min(ple_i.y1, ple_j.y1);
				ple_i.y2 = std::max(ple_i.y2, ple_j.y2);

				ple[j--] = ple[--n];

				updated_i = true;
			}

			if (updated_i)
			{
				done = false;
			}
			else
			{
				ple_i.done = true;
			}
		}
	}

	std::sort(ple, ple + n);

	put_uint(n); std::cout.put('\n');

	for (uint i = 0; i < n; ++i)
	{
		put_uint(ple[i].x1); std::cout.put(' ');
		put_uint(ple[i].x2); std::cout.put(' ');

		put_uint(ple[i].y1); std::cout.put(' ');
		put_uint(ple[i].y2); std::cout.put('\n');
	}

	return 0;
}