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import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import java.util.ListIterator;
import java.util.StringTokenizer;


public class ple {
	
	public static String solve(Reader in) throws IOException {
		int num = in.nextInt();
		
		Plemie[] all = new Plemie[num];
		for (int i=0; i<num; i++) {
			all[i] = new Plemie(in.nextInt(), in.nextInt(), in.nextInt(), in.nextInt());
		}
		
		Arrays.sort(all, new x1Comparator());
		
		boolean changes = true;
		while (changes) {
			changes = false;
			
			for (int left = 0; left < num-1; left++) {
				Plemie leftPlemie = all[left];
				if (leftPlemie != null) {
					for (int next = left + 1; next < num; next++) {
						Plemie nextPlemie = all[next];
						if (nextPlemie != null) {
							if (xOverlaps(leftPlemie, nextPlemie)) {
								if (yOverlaps(leftPlemie, nextPlemie)) {
									// merge
									merge(leftPlemie, nextPlemie);
									all[next] = null;
									changes = true;
								}
							} else {
								break;	// koniec nakladajacego sie przedzialu iksa
							}
						}
					}
				}
			}
			
			
			
		}
		
		Arrays.sort(all, new finalComparator());
		StringBuilder sb = new StringBuilder();
		int count = 0;
		for (Plemie p: all) {
			if (p == null) continue;
			count++;
			sb.append("\n");
			sb.append(p.x1);
			sb.append(" ");
			sb.append(p.x2);
			sb.append(" ");
			sb.append(p.y1);
			sb.append(" ");
			sb.append(p.y2);
		}
		
		return count +  sb.toString();
	}
	
	private static void merge(Plemie leftPlemie, Plemie nextPlemie) {
		leftPlemie.x1 = Math.min(leftPlemie.x1, nextPlemie.x1);
		leftPlemie.y1 = Math.min(leftPlemie.y1, nextPlemie.y1);
		leftPlemie.x2 = Math.max(leftPlemie.x2, nextPlemie.x2);
		leftPlemie.y2 = Math.max(leftPlemie.y2, nextPlemie.y2);;
	}

	private static boolean yOverlaps(Plemie leftPlemie, Plemie nextPlemie) {
		return leftPlemie.y1 < nextPlemie.y2 && leftPlemie.y2 > nextPlemie.y1;
	}

	private static boolean xOverlaps(Plemie leftPlemie, Plemie nextPlemie) {
		return leftPlemie.x1 < nextPlemie.x2 && leftPlemie.x2 > nextPlemie.x1;
	}

	private static class x1Comparator implements Comparator<Plemie> {
		@Override
		public int compare(Plemie o1, Plemie o2) {
			return o1.x1.compareTo(o2.x1);
		}
	}
	
	private static class finalComparator implements Comparator<Plemie> {
		@Override
		public int compare(Plemie o1, Plemie o2) {
			if (o1 == null) {
				return -1;
			} else if (o2 == null) {
				return 1;
			} else if (o1.x1.compareTo(o2.x1) != 0) {
				return o1.x1.compareTo(o2.x1);
			} else if (o1.x2.compareTo(o2.x2) != 0) {
				return o1.x2.compareTo(o2.x2);
			} else if (o1.y1.compareTo(o2.y1) != 0) {
				return o1.y1.compareTo(o2.y1);
			} else {
				return o1.y2.compareTo(o2.y2);
			}
		}
	}
	
	private static class Plemie {
		Integer x1;
		Integer x2;
		Integer y1;
		Integer y2;
		
		public Plemie(Integer x1, Integer x2, Integer y1, Integer y2) {
			this.x1 = x1;
			this.x2 = x2;
			this.y1 = y1;
			this.y2 = y2;
		}

		@Override
		public String toString() {
			return "Plemie [x1=" + x1 + ", x2=" + x2 + ", y1=" + y1 + ", y2="
					+ y2 + "]";
		}
		
		
	}
	
	

	public static void main(String[] args) throws IOException {
		Reader reader = new Reader(System.in);
		Writer writer = new Writer(System.out);
		String solution = solve(reader); 
		writer.println(solution);
		writer.flush();

	}

	/** Class for buffered reading int and double values */
	public static class Reader {
		BufferedReader reader;
		StringTokenizer tokenizer;

		public Reader(InputStream input) {
			reader = new BufferedReader(new InputStreamReader(input));
			tokenizer = new StringTokenizer("");
		}

		/** get next word */
		String next() throws IOException {
			while (!tokenizer.hasMoreTokens()) {
				String str = reader.readLine();
				if (str == null) {
					return null;
				}
				tokenizer = new StringTokenizer(str);
			}
			return tokenizer.nextToken();
		}

		int nextInt() throws IOException {
			return Integer.parseInt(next());
		}

		double nextDouble() throws IOException {
			return Double.parseDouble(next());
		}
	}

	/** Class for buffered writing int and double values */
	public static class Writer {
		BufferedWriter writer;

		public Writer(OutputStream out) {
			writer = new BufferedWriter(new OutputStreamWriter(out), 512);
		}
		
		void print(char c) throws IOException {
			writer.write(c);
		}

		void print(String str) throws IOException {
			writer.write(str);
		}

		void println(String str) throws IOException {
			writer.write(str);
			writer.write("\n");
		}

		void println() throws IOException {
			writer.write("\n");
		}

		void flush() throws IOException {
			writer.flush();
		}

		@Override
		protected void finalize() {
			try {
				writer.flush();
			} catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
	}


}