description: You have an array of integers (initially empty).
  
  You have to perform q queries. Each query is of one of two types: 
  
    * "1 x" — add the element x to the end of the array; 
    * "2 x y" — replace all occurrences of x in the array with y. 
  
  
  
  Find the resulting array after performing all the queries.
  
  Input
  
  The first line contains a single integer q (1 ≤ q ≤ 5 ⋅ 10^5) — the number of queries.
  
  Next q lines contain queries (one per line). Each query is of one of two types: 
  
    * "1 x" (1 ≤ x ≤ 5 ⋅ 10^5); 
    * "2 x y" (1 ≤ x, y ≤ 5 ⋅ 10^5). 
  
  
  
  It's guaranteed that there is at least one query of the first type.
  
  Output
  
  In a single line, print k integers — the resulting array after performing all the queries, where k is the number of queries of the first type.
  
  Examples
  
  Input
  
  
  7
  1 3
  1 1
  2 1 2
  1 2
  1 1
  1 2
  2 1 3
  
  
  Output
  
  
  3 2 2 3 2 
  
  Input
  
  
  4
  1 1
  1 2
  1 1
  2 2 2
  
  
  Output
  
  
  1 2 1 
  
  Input
  
  
  8
  2 1 4
  1 1
  1 4
  1 2
  2 2 4
  2 4 3
  1 2
  2 2 7
  
  
  Output
  
  
  1 3 3 7 
  
  Note
  
  In the first example, the array changes as follows:
  
  [] → [3] → [3, 1] → [3, 2] → [3, 2, 2] → [3, 2, 2, 1] → [3, 2, 2, 1, 2] → [3, 2, 2, 3, 2].
  
  In the second example, the array changes as follows:
  
  [] → [1] → [1, 2] → [1, 2, 1] → [1, 2, 1].
  
  In the third example, the array changes as follows:
  
  [] → [] → [1] → [1, 4] → [1, 4, 2] → [1, 4, 4] → [1, 3, 3] → [1, 3, 3, 2] → [1, 3, 3, 7].
solution: import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.io.PrintWriter;
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.StringTokenizer;
  import java.util.TreeSet;
  
  public class E {
  
  	public static void main(String[] args) {
  		FastScanner fs=new FastScanner();
  		int q=fs.nextInt();
  		TreeSet<Node> nodes=new TreeSet<>();
  		ArrayList<Node> roots=new ArrayList<>();
  		PrintWriter out=new PrintWriter(System.out);
  		for (int qq=0; qq<q; qq++) {
  			int type=fs.nextInt();
  			if (type==1) {
  				int val=fs.nextInt();
  				Node me=getIfExists(nodes, val);
  				roots.add(me);
  			}
  			else {
  				int fromI=fs.nextInt();
  				int toI=fs.nextInt();
  				if (fromI==toI) continue;
  				Node newFrom=getIfExists(nodes, fromI);
  				Node newTo=getIfExists(nodes, toI);
  				newFrom.par=newTo;
  			}
  		}
  		for (Node nn:roots) {
  			out.print(nn.getPar().value+" ");
  		}
  		out.println();
  		out.close();
  	}
  	
  	static Node getIfExists(TreeSet<Node> nodes, int val) {
  		Node test=new Node(val);
  		if (nodes.contains(test)) {
  			Node toReturn=nodes.ceiling(test);
  			if (toReturn.par!=null) {
  				nodes.remove(toReturn);
  				nodes.add(test);
  				return test;
  			}
  			return toReturn;
  		}
  		nodes.add(test);
  		return test; 
  	}
  	
  	
  	static class Node implements Comparable<Node> {
  		Node par;
  		int value;
  		
  		public Node(int value) {
  			this.value=value;
  		}
  		
  		public int compareTo(Node o) {
  			return Integer.compare(value, o.value);
  		}
  		Node getPar() {
  			if (par==null) return this;
  			return par=par.getPar();
  		}
  	}
  	
  
  	static void sort(int[] a) {
  		ArrayList<Integer> l=new ArrayList<>();
  		for (int i:a) l.add(i);
  		Collections.sort(l);
  		for (int i=0; i<a.length; i++) a[i]=l.get(i);
  	}
  	
  	static class FastScanner {
  		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
  		StringTokenizer st=new StringTokenizer("");
  		String next() {
  			while (!st.hasMoreTokens())
  				try {
  					st=new StringTokenizer(br.readLine());
  				} catch (IOException e) {
  					e.printStackTrace();
  				}
  			return st.nextToken();
  		}
  		
  		int nextInt() {
  			return Integer.parseInt(next());
  		}
  		int[] readArray(int n) {
  			int[] a=new int[n];
  			for (int i=0; i<n; i++) a[i]=nextInt();
  			return a;
  		}
  		long nextLong() {
  			return Long.parseLong(next());
  		}
  	}
  
  	
  }
  