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import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.StringTokenizer;


public class ple {

	public static void main(String[] args) throws IOException {
		
		ple solver = new ple();
		solver.init();
		solver.solve();
	}
	
	private void init() {
		
	}
	
	private static class Rect implements Comparable<Rect>{
		int x1,x2,y1,y2;
		
		int spreadedBy = -1;

		public Rect(int x1, int x2, int y1, int y2) {
			super();
			this.x1 = x1;
			this.x2 = x2;
			this.y1 = y1;
			this.y2 = y2;
		}
		
		public boolean cross(Rect r) {
			if ((x1 >= r.x1 && x1 < r.x2) || (r.x1 >= x1 && r.x1 < x2)) {
				if ((y1 >= r.y1 && y1 < r.y2) || (r.y1 >= y1 && r.y1 < y2)) {
					return true;
				}
			}
			return false;
		}
		
		public void spread(Rect r) {
			this.x1 = Math.min(this.x1, r.x1);
			this.x2 = Math.max(this.x2, r.x2);
			this.y1 = Math.min(this.y1, r.y1);
			this.y2 = Math.max(this.y2, r.y2);
		}

		@Override
		public int compareTo(Rect rect) {
			if (this.x1 == rect.x1) {
				if (this.x2 == rect.x2) {
					if (this.y1 == rect.y1) {
						return this.y2 - rect.y2;
					} else {
						return this.y1 - rect.y1;
					}
				} else {
					return this.x2 - rect.x2;
				}
			} else {
				return this.x1 - rect.x1;
			}
		}
	}
	
	private void solve() throws IOException { 
		Reader in = new Reader(System.in);
		PrintWriter out = new PrintWriter(new BufferedOutputStream(System.out));
		
		int n = in.nextInt();
		Rect[] rects2 = new Rect[n];
		for (int i = 0 ; i < rects2.length; i++) {
			rects2[i] = new Rect(in.nextInt(), in.nextInt(), in.nextInt(), in.nextInt());
		}
		
		List<Integer> order = new ArrayList<Integer>(n);
		for (int i = 0; i < n; i++) order.add(i);
		Collections.shuffle(order);
		
		Rect[] rects = new Rect[n];
		int rectsI = 0;
		for (Integer idx : order) {
			rects[rectsI++] = rects2[idx];
		}
		
		Set<Integer> toUse = new HashSet<Integer>();
		for (int i = 0; i < n; i++) toUse.add(i);
		Set<Integer> newRects = new HashSet<Integer>();
		
		for (int i = 0; i < n; i++) {
			for (int j = i + 1; j < n; j++) {
				if(rects[i].cross(rects[j])) {
					if (rects[j].spreadedBy == -1) {
						rects[i].spread(rects[j]);
						newRects.add(i);
						toUse.remove(j);
						rects[j].spreadedBy = i;
					} else {
						rects[rects[j].spreadedBy].spread(rects[i]);
						toUse.remove(i);
						rects[i].spreadedBy = rects[j].spreadedBy;
						break;
					}
				}
			}
		}
		
		while (!newRects.isEmpty()) {
			Set<Integer> usedRects = new HashSet<Integer>();
			Set<Integer> toRemove = new HashSet<Integer>();
			for (Integer i : newRects) if (rects[i].spreadedBy == -1) {
				for (int j : toUse) if (!i.equals(j)) {
					if (rects[i].cross(rects[j])) {
						if (rects[j].spreadedBy == -1) {
							rects[i].spread(rects[j]);
							usedRects.add(i);
							toRemove.add(j);
							rects[j].spreadedBy = i;
						} else {
							rects[rects[j].spreadedBy].spread(rects[i]);
							toRemove.add(i);
							rects[i].spreadedBy = rects[j].spreadedBy;
							break;
						}
					}
				}
			}
			for (Integer i : toRemove) toUse.remove(i);
			newRects = usedRects;
		}
		
		//TODO sort lexigography and print toUse
		Rect[] ans = new Rect[toUse.size()];
		int i = 0;
		for (Integer idx : toUse) {
			ans[i++] = rects[idx]; 
		}
		Arrays.sort(ans);
		out.println(ans.length);
		for (Rect r : ans) {
			out.println(r.x1 + " " + r.x2 + " " + r.y1 + " " + r.y2);
		}
		
		out.flush();
		out.close();
	}
	
	private static class Reader {
	    BufferedReader reader;
	    StringTokenizer tokenizer;

	    /** call this method to initialize reader for InputStream */
	    Reader(InputStream input) {
	        reader = new BufferedReader(
	                     new InputStreamReader(input) );
	        tokenizer = new StringTokenizer("");
	    }

	    public void skipLine() throws IOException {
			reader.readLine();
		}

		/** get next word */
	    public String next() throws IOException {
	        while ( ! tokenizer.hasMoreTokens() ) {
	            //TODO add check for eof if necessary
	            tokenizer = new StringTokenizer(
	                   reader.readLine() );
	        }
	        return tokenizer.nextToken();
	    }

	    public int nextInt() throws IOException {
	        return Integer.parseInt( next() );
	    }
	    
	    public double nextDouble() throws IOException {
	        return Double.parseDouble( next() );
	    }
	    
	    public long nextLong() throws IOException {
	    	return Long.parseLong(next());
	    }
	}
}