description: This is the easy version of the problem. The only difference between the two versions is the constraint on n. You can make hacks only if all versions of the problem are solved.
  
  A forest is an undirected graph without cycles (not necessarily connected).
  
  Mocha and Diana are friends in Zhijiang, both of them have a forest with nodes numbered from 1 to n, and they would like to add edges to their forests such that: 
  
    * After adding edges, both of their graphs are still forests. 
    * They add the same edges. That is, if an edge (u, v) is added to Mocha's forest, then an edge (u, v) is added to Diana's forest, and vice versa. 
  
  
  
  Mocha and Diana want to know the maximum number of edges they can add, and which edges to add.
  
  Input
  
  The first line contains three integers n, m_1 and m_2 (1 ≤ n ≤ 1000, 0 ≤ m_1, m_2 < n) — the number of nodes and the number of initial edges in Mocha's forest and Diana's forest.
  
  Each of the next m_1 lines contains two integers u and v (1 ≤ u, v ≤ n, u ≠ v) — the edges in Mocha's forest.
  
  Each of the next m_2 lines contains two integers u and v (1 ≤ u, v ≤ n, u ≠ v) — the edges in Diana's forest.
  
  Output
  
  The first line contains only one integer h, the maximum number of edges Mocha and Diana can add (in each forest).
  
  Each of the next h lines contains two integers u and v (1 ≤ u, v ≤ n, u ≠ v) — the edge you add each time.
  
  If there are multiple correct answers, you can print any one of them.
  
  Examples
  
  Input
  
  
  3 2 2
  1 2
  2 3
  1 2
  1 3
  
  
  Output
  
  
  0
  
  
  Input
  
  
  5 3 2
  5 4
  2 1
  4 3
  4 3
  1 4
  
  
  Output
  
  
  1
  2 4
  
  
  Input
  
  
  8 1 2
  1 7
  2 6
  1 5
  
  
  Output
  
  
  5
  5 2
  2 3
  3 4
  4 7
  6 8
  
  Note
  
  In the first example, we cannot add any edge.
  
  In the second example, the initial forests are as follows.
  
  <image>
  
  We can add an edge (2, 4).
  
  <image>
solution: import java.io.*;
  import java.util.*;
  
   
  public class Practice
  {
  	static final int mod=1000000007;
  	static FastReader sc=new FastReader(System.in);
  //	static Reader sc=new Reader();
  	static  PrintWriter out=new PrintWriter(System.out);
  	public static void main(String[] args) throws IOException
  	{ 
  		int t=1;
  //		t=sc.nextInt();
  //		StringBuilder sb=new StringBuilder();
  		while(t-->0)
  		{
  			solve();
  //			sb.append("\n");
  		}
  //		out.print(sb);
  		out.close();
  		out.flush();
  	}
  	static void solve() throws IOException
  	{
  		int n=sc.nextInt();
  		int a=sc.nextInt(),b=sc.nextInt();
  		DisjointUnionSets mocha=new DisjointUnionSets(n);
  		DisjointUnionSets diana=new DisjointUnionSets(n);
  		for(int i=0;i<a;i++)
  		{
  			int e=sc.nextInt()-1,v=sc.nextInt()-1;
  			mocha.union(e, v);
  		}
  		for(int i=0;i<b;i++)
  		{
  			int e=sc.nextInt()-1,v=sc.nextInt()-1;
  			diana.union(e, v);
  		}
  		int count=0;
  		StringBuilder sb=new StringBuilder();
  		for(int i=0;i<n;i++)
  		for(int j=0;j<n;j++)
  		{
  			if(mocha.find(i)!=mocha.find(j) && diana.find(i)!=diana.find(j))
  			{
  //				out.println("ver "+i);
  				count++;
  				sb.append((i+1)+" "+(j+1)+"\n");
  				mocha.union(i, j);
  				diana.union(i, j);
  			}
  		}
  		out.println(count);
  		out.print(sb);
  	}
  	static class DisjointUnionSets 
  	{
  	    int[] rank, parent;
  	    int n;
  	    // Constructor
  	    public DisjointUnionSets(int n)
  	    {
  	        rank = new int[n];
  	        parent = new int[n];
  	        this.n = n;
  	        makeSet();
  	    }
  	    // Creates n sets with single item in each
  	    void makeSet()
  	    {
  	        for (int i = 0; i < n; i++)
  	            parent[i] = i;
  	    }
  	    int find(int x)
  	    {
  	        if (parent[x] != x) {
  	            parent[x] = find(parent[x]);
  	        }
  	        return parent[x];
  	    }
  	    // Unites the set that includes x and the set
  	    // that includes x
  	    void union(int x, int y)
  	    {
  	        int xRoot = find(x), yRoot = find(y);
  	        if (xRoot == yRoot)
  	            return;
  	        if (rank[xRoot] < rank[yRoot])
  	            parent[xRoot] = yRoot;
  	        else if (rank[yRoot] < rank[xRoot])
  	        	parent[yRoot] = xRoot;
  	        else // if ranks are the same
  	        {
  	        	parent[yRoot] = xRoot;
  	            rank[xRoot] = rank[xRoot] + 1;
  	        }
  	    }
  	}
  	static class Node
  	{
  		int vertex;
  		ArrayList<Node> adj;
  		int dist[];
  		Node parent;
  		Node(int v,int k)
  		{
  			vertex=v;
  			adj=new ArrayList<Node>();
  			dist=new int[k+1];
  		}
  		@Override
  		public String toString() 
  		{
  			return vertex+" ";
  		}
  	}
  	static class Edge
  	{
  		Node ver;
  //		int weight;
  		Edge(Node v)
  		{
  			this.ver=v;
  //			weight=w;
  		}
  		@Override
  		public String toString() 
  		{
  			return ver.vertex+"";
  		}
  	}
  	static long power(long x, long y)
  	  {
  	    long res = 1; 
  	    x = x % mod; 
  	    if (x == 0)
  	      return 0; 
  	    while (y > 0)
  	    {
  	    	if ((y & 1) != 0)
  	    		res = (res * x) % mod;
  	    	
  	    	y = y >> 1; // y = y/2
  	    	x = (x * x) % mod;
  	    }
  	    return res;
  	  }
  	static long binomialCoeff(long n, long k)
      {
          long res = 1;
          if(k>n)
          	return 0;
          // Since C(n, k) = C(n, n-k)
          if (k > n - k)
              k = n - k;
   
          // Calculate value of
          // [n * (n-1) *---* (n-k+1)] / [k * (k-1) *----* 1]
          for (long i = 0; i < k; ++i) {
              res *= (n - i);
              res /= (i + 1);
          }
   
          return res;
      }
  	static class FastReader
  	{
          byte[] buf = new byte[2048];
          int index, total;
          InputStream in;
   
          FastReader(InputStream is) 
          {
              in = is;
          }
   
          int scan() throws IOException 
          {
              if (index >= total) {
                  index = 0;
                  total = in.read(buf);
                  if (total <= 0) {
                      return -1;
                  }
              }
              return buf[index++];
          }
   
          String next() throws IOException 
          {
              int c;
              for (c = scan(); c <= 32; c = scan());
              StringBuilder sb = new StringBuilder();
              for (; c > 32; c = scan()) {
                  sb.append((char) c);
              }
              return sb.toString();
          }
   
          int nextInt() throws IOException 
          {
              int c, val = 0;
              for (c = scan(); c <= 32; c = scan());
              boolean neg = c == '-';
              if (c == '-' || c == '+') {
                  c = scan();
              }
              for (; c >= '0' && c <= '9'; c = scan()) {
                  val = (val << 3) + (val << 1) + (c & 15);
              }
              return neg ? -val : val;
          }
   
          long nextLong() throws IOException 
          {
              int c;
              long val = 0;
              for (c = scan(); c <= 32; c = scan());
              boolean neg = c == '-';
              if (c == '-' || c == '+') {
                  c = scan();
              }
              for (; c >= '0' && c <= '9'; c = scan()) {
                  val = (val << 3) + (val << 1) + (c & 15);
              }
              return neg ? -val : val;
          }
      }
  	static class Reader 
  	{
          final private int BUFFER_SIZE = 1 << 16;
          private DataInputStream din;
          private byte[] buffer;
          private int bufferPointer, bytesRead;
   
          public Reader()
          {
              din = new DataInputStream(System.in);
              buffer = new byte[BUFFER_SIZE];
              bufferPointer = bytesRead = 0;
          }
   
          public Reader(String file_name) throws IOException
          {
              din = new DataInputStream(
                  new FileInputStream(file_name));
              buffer = new byte[BUFFER_SIZE];
              bufferPointer = bytesRead = 0;
          }
   
          public String readLine() throws IOException
          {
              byte[] buf = new byte[64]; // line length
              int cnt = 0, c;
              while ((c = read()) != -1) {
                  if (c == '\n') {
                      if (cnt != 0) {
                          break;
                      }
                      else {
                          continue;
                      }
                  }
                  buf[cnt++] = (byte)c;
              }
              return new String(buf, 0, cnt);
          }
   
          public int nextInt() throws IOException
          {
              int ret = 0;
              byte c = read();
              while (c <= ' ') {
                  c = read();
              }
              boolean neg = (c == '-');
              if (neg)
                  c = read();
              do {
                  ret = ret * 10 + c - '0';
              } while ((c = read()) >= '0' && c <= '9');
   
              if (neg)
                  return -ret;
              return ret;
          }
   
          public long nextLong() throws IOException
          {
              long ret = 0;
              byte c = read();
              while (c <= ' ')
                  c = read();
              boolean neg = (c == '-');
              if (neg)
                  c = read();
              do {
                  ret = ret * 10 + c - '0';
              } while ((c = read()) >= '0' && c <= '9');
              if (neg)
                  return -ret;
              return ret;
          }
   
          public double nextDouble() throws IOException
          {
              double ret = 0, div = 1;
              byte c = read();
              while (c <= ' ')
                  c = read();
              boolean neg = (c == '-');
              if (neg)
                  c = read();
   
              do {
                  ret = ret * 10 + c - '0';
              } while ((c = read()) >= '0' && c <= '9');
   
              if (c == '.') {
                  while ((c = read()) >= '0' && c <= '9') {
                      ret += (c - '0') / (div *= 10);
                  }
              }
   
              if (neg)
                  return -ret;
              return ret;
          }
   
          private void fillBuffer() throws IOException
          {
              bytesRead = din.read(buffer, bufferPointer = 0,
                                   BUFFER_SIZE);
              if (bytesRead == -1)
                  buffer[0] = -1;
          }
   
          private byte read() throws IOException
          {
              if (bufferPointer == bytesRead)
                  fillBuffer();
              return buffer[bufferPointer++];
          }
   
          public void close() throws IOException
          {
              if (din == null)
                  return;
              din.close();
          }
          public void printarray(int arr[])
          {
          	for (int i = 0; i < arr.length; i++)
  				System.out.print(arr[i]+" ");
          	System.out.println();
          }
      }
  }
  
  
  
  
  
  
  
  
  