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import java.io.IOException;
import java.io.InputStream;
import java.util.Arrays;
import java.util.Comparator;

public class ple {
	private static int skipWS(final InputStream in) throws IOException {
		int val = -1;
		while ((val = in.read()) != -1) {
			if (!Character.isWhitespace((char) val))
				break;
		}
		return val;
	}

	private static int readInt(final InputStream in) {
		try {
			final StringBuilder b = new StringBuilder();
			int val = skipWS(in);
			b.append((char) val);
			while ((val = in.read()) != -1) {
				if (Character.isWhitespace((char) val))
					break;
				b.append((char) val);
			}
			return Integer.parseInt(b.toString());
		} catch (final IOException e) {
			throw new RuntimeException(e);
		}
	}

	public static void main(String[] args) throws Exception {
		final int n = readInt(System.in);
		MyList<Rect> rects = new MyList<>();
		for (int i = 0; i < n; i++) {
			rects.add(new Rect());
		}
		Node<Rect> nav1 = rects.tail;
		Node<Rect> nav2;
		first: while (nav1 != null) {
			nav2 = nav1.next;
			while (nav2 != null) {
				if (nav2.element.intersects(nav1.element)) {
					nav2.element.merge(nav1.element);
					rects.mergeNavs(nav1, nav2);
					nav1 = nav2;
					continue first;
				}
				nav2 = nav2.next;
			}
			nav1 = nav1.next;
		}
		Rect[] toSort = new Rect[rects.size];
		nav1 = rects.tail;
		for (int i = 0; i < rects.size; i++) {
			toSort[i] = nav1.element;
			nav1 = nav1.next;
		}
		Arrays.sort(toSort, new RectComparator());
		System.out.println(toSort.length);
		for (int i = 0; i < toSort.length; i++) {
			System.out.println(toSort[i]);
		}
	}

	private static class RectComparator implements Comparator<Rect> {

		@Override
		public int compare(Rect r1, Rect r2) {
			int result = r1.x1 - r2.x1;
			if (result == 0) result = r1.x2 - r2.x2;
			if (result == 0) result = r1.y1 - r2.y1;
			if (result == 0) result = r1.y2 - r2.y2;
			return result;
		}
	}

	private static class Rect {
		int x1, y1, x2, y2;

		Rect() {
			x1 = readInt(System.in);
			x2 = readInt(System.in);
			y1 = readInt(System.in);
			y2 = readInt(System.in);
		}

		boolean intersects(Rect that) {
			if (x1 >= that.x1 && x2 <= that.x2 && y1 >= that.y1 && y2 <= that.y2) return true; //embedded
			if (that.x1 >= x1 && that.x2 <= x2 && that.y1 >= y1 && that.y2 <= y2) return true; //embedded
			boolean startsX = x1 >= that.x1 && x1 <= that.x2;
			boolean endsX = x2 >= that.x1 && x2 <= that.x2;
			boolean startsY = y1 >= that.y1 && y1 <= that.y2;
			boolean endsY = y2 >= that.y1 && y2 <= that.y2;
			return (startsX || endsX) && (startsY || endsY);
		}

		void merge(Rect that) {
			if (that.x1 < this.x1) this.x1 = that.x1;
			if (that.x2 > this.x2) this.x2 = that.x2;
			if (that.y1 < this.y1) this.y1 = that.y1;
			if (that.y2 > this.y2) this.y2 = that.y2;
		}

		@Override
		public String toString() {
			return x1 + " " + x2 + " " + y1 + " " + y2;
		}
	}

	private static class MyList<T> {
		Node<T> head;
		Node<T> tail;
		int size = 0;

		void add(T element) {
			if (head == null) {
				head = new Node<>(element);
				tail = head;
			} else {
				Node<T> newNode = new Node<>(element);
				head.next = newNode;
				newNode.prev = head;
				head = newNode;
			}
			size++;
		}

		void mergeNavs(Node<T> nav1, Node<T> nav2) {
			if (size == 2) {
				nav2.next = null;
				nav2.prev = null;
				head = nav2;
				tail = nav2;
			} else { //more than 2 elements
				Node<T> newTail = nav1.next;
				Node<T> newHead = nav1.prev != null ? nav1.prev : head;
				newTail.prev = null;
				newHead.next = null;
				if (head != newHead) head.next = tail;
				if (tail != newTail) tail.prev = head;
				head = newHead;
				tail = newTail;
			}
			size--;
		}

		@Override
		public String toString() {
			if (head == null) return "[]";
			StringBuffer result = new StringBuffer("[");
			Node<T> ptr = tail;
			while (ptr != null) {
				result.append(ptr.element).append(", ");
				ptr = ptr.next;
			}
			result.append(']');
			return result.toString();
		}
	}

	private static class Node<T> {
		T element;
		Node<T> prev;
		Node<T> next;
		Node(T element) {
			this.element = element;
		}
		@Override
		public String toString() {
			return element.toString();
		}
	}
}