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.OutputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.PrintWriter;
  import java.io.BufferedReader;
  import java.io.InputStreamReader;
  import java.util.*;
  
  public class Main {
      public static void main(String[] args){
          InputStream inputStream = System.in;
          OutputStream outputStream = System.out;
          InputReader in = new InputReader(inputStream);
          PrintWriter out = new PrintWriter(outputStream);
          solve(in, out);
          out.close();
      }
  
      static String reverse(String s) {
          return (new StringBuilder(s)).reverse().toString();
      }
  
      static void sieveOfEratosthenes(int n, int factors[], ArrayList<Integer> ar) 
      { 
          factors[1]=1;
          int p;
          for(p = 2; p*p <=n; p++) 
          { 
              if(factors[p] == 0) 
              { 
                  ar.add(p);
                  factors[p]=p;
                  for(int i = p*p; i <= n; i += p) 
                      if(factors[i]==0)
                          factors[i] = p; 
              } 
          } 
          for(;p<=n;p++){
              if(factors[p] == 0) 
              { 
                  factors[p] = p;
                  ar.add(p);
              } 
          }
      }
  
      static void sort(int ar[]) {
          int n = ar.length;
          ArrayList<Integer> a = new ArrayList<>();
          for (int i = 0; i < n; i++)
              a.add(ar[i]);
          Collections.sort(a);
          for (int i = 0; i < n; i++)
              ar[i] = a.get(i);
      }
  
      static void sort1(long ar[]) {
          int n = ar.length;
          ArrayList<Long> a = new ArrayList<>();
          for (int i = 0; i < n; i++)
              a.add(ar[i]);
          Collections.sort(a);
          for (int i = 0; i < n; i++)
              ar[i] = a.get(i);
      }
  
      static void sort2(char ar[]) {
          int n = ar.length;
          ArrayList<Character> a = new ArrayList<>();
          for (int i = 0; i < n; i++)
              a.add(ar[i]);
          Collections.sort(a);
          for (int i = 0; i < n; i++)
              ar[i] = a.get(i);
      }
  
      static long ncr(long n, long r, long mod) {
          if (r == 0)
              return 1;
          long val = ncr(n - 1, r - 1, mod);
          val = (n * val) % mod;
          val = (val * modInverse(r, mod)) % mod;
          return val;
      }
  
      // static long gcd[];
      
      // static void build(long a[], int v, int tl, int tr) {
      //     if (tl == tr) {
      //         gcd[v] = a[tl];
              
      //     } else {
      //         int tm = (tl + tr) / 2;
      //         build(a, v*2, tl, tm);
      //         build(a, v*2+1, tm+1, tr);
      //         gcd[v] = gcd(gcd[v*2], gcd[v*2+1]);
      //     }
      // }
  
      // static void push(int v, int tl, int tr){
      //     if(tl==tr){
      //         lz[v] = 0;
      //         return;
      //     }
      //     min[2*v] += lz[v];
      //     min[2*v+1] += lz[v];
      //     lz[2*v] += lz[v];
      //     lz[2*v+1] += lz[v];
      //     lz[v] = 0;
      // }
  
      // static void update(int v, int tl, int tr, int l, int r, int val) {
      //     push(v,tl,tr);
      //     if(tl>r||tr<l)
      //         return;
      //     if(tl>=l&&tr<=r){
      //         min[v] += val;
      //         lz[v] += val;
      //         return;
      //     }
      //     int tm = (tl + tr) / 2;
      //     update(v*2, tl, tm, l, r, val);
      //     update(v*2+1, tm+1, tr, l, r, val);
      //     min[v] = Math.min(min[2*v],min[2*v+1]);
      // }
  
      // static long get(int v, int tl, int tr, int l, int r) {
      //     if (tl >= l && tr <= r) {
      //         return gcd[v];
      //     }
      //     int tm = (tl + tr) / 2;
      //     if(l>tm){
      //         return get(2*v+1, tm+1, tr, l, r);
      //     }
      //     if(r<tm+1){
      //         return get(2*v, tl, tm, l, r);
      //     }
      //     return gcd(get(2*v, tl, tm, l, r), get(2*v+1, tm+1, tr, l, r));
      // }
  
      // static int y = 0;
  
      static int parent[];
      static int rank[];
  
      static int find_set(int v) {
          if (v == parent[v])
              return v;
          return find_set(parent[v]);
      }
      
      static void make_set(int v) {
          parent[v] = v;
          rank[v] = 0;
      }
      
      static void union_sets(int a, int b) {
          a = find_set(a);
          b = find_set(b);
          if (a != b) {
              if (rank[a] < rank[b]){
                  int tmp = a;
                  a = b;
                  b = tmp;
              }
              parent[b] = a;
              if (rank[a] == rank[b])
                  rank[a]++;
          }
      }
  
      static int parent1[];
      static int rank1[];
  
      static int find_set1(int v) {
          if (v == parent1[v])
              return v;
          return find_set1(parent1[v]);
      }
      
      static void make_set1(int v) {
          parent1[v] = v;
          rank1[v] = 0;
      }
      
      static void union_sets1(int a, int b) {
          a = find_set1(a);
          b = find_set1(b);
          if (a != b) {
              if (rank1[a] < rank1[b]){
                  int tmp = a;
                  a = b;
                  b = tmp;
              }
              parent1[b] = a;
              if (rank1[a] == rank1[b])
                  rank1[a]++;
          }
      }
  
      public static void solve(InputReader sc, PrintWriter pw){
          int i, j = 0;
          int t = 1; 
          long mod = 1000000007;
          // int t = sc.nextInt();
          u: while (t-- > 0) {
              int n = sc.nextInt();
              int m1 = sc.nextInt();
              int m2 = sc.nextInt();
              parent = new int[n];
              rank = new int[n];
              for(i=0;i<n;i++){
                  make_set(i);
              }
              for(i=0;i<m1;i++){
                  int y = sc.nextInt();
                  int z = sc.nextInt();
                  union_sets(y-1, z-1);
              }
              parent1 = new int[n];
              rank1 = new int[n];
              for(i=0;i<n;i++){
                  make_set1(i);
              }
              for(i=0;i<m2;i++){
                  int y = sc.nextInt();
                  int z = sc.nextInt();
                  union_sets1(y-1, z-1);
              }
              // for(i=0;i<n;i++){
              //     pw.println(i+" "+find_set1(i));
              // }
              int y = 0;
              ArrayList<Integer> ar = new ArrayList<>();
              for(i=0;i<n;i++){
                  for(j=i+1;j<n;j++){
                      // pw.println(find_set(i)+" "+find_set(j)+" "+find_set1(i)+" "+find_set1(j));
                      if(find_set(i)!=find_set(j)&&find_set1(i)!=find_set1(j)){
                          union_sets(i, j);
                          union_sets1(i, j);
                          y++;
                          ar.add(i+1);
                          ar.add(j+1);
                      }
                  }
              }
              pw.println(y);
              for(i=0;i<y;i++){
                  pw.println(ar.get(2*i)+" "+ar.get(2*i+1));
              }
          }
      }
  
  
      static void KMPSearch(char pat[], char txt[], int pres[])
      {
          int M = pat.length;
          int N = txt.length;
          int lps[] = new int[M];
          int j = 0; 
          computeLPSArray(pat, M, lps);
          int i = 0;
          while (i < N) {
              if (pat[j] == txt[i]) {
                  j++;
                  i++;
              }
              if (j == M) {
                  pres[i-1] = 1;
                  j = lps[j - 1];
              }
              else if (i < N && pat[j] != txt[i]) {
                  if (j != 0)
                      j = lps[j - 1];
                  else
                      i = i + 1;
              }
          }
      }
    
      static void computeLPSArray(char pat[], int M, int lps[])
      {
          int len = 0;
          int i = 1;
          lps[0] = 0; 
          while (i < M) {
              if (pat[i] == pat[len]) {
                  len++;
                  lps[i] = len;
                  i++;
              }
              else 
              {
                  if (len != 0) {
                      len = lps[len - 1];
                  }
                  else
                  {
                      lps[i] = len;
                      i++;
                  }
              }
          }
      }
  
      static long[][] matrixMult(long a[][], long b[][], long mod){
          int n = a.length;
          int m = a[0].length;
          int p = b[0].length;
          long c[][] = new long[n][p];
          for(int i=0;i<n;i++){
              for(int j=0;j<m;j++){
                  for(int k=0;k<p;k++){
                      c[i][k] += a[i][j]*b[j][k];
                      c[i][k] %= mod;
                  }
              }
          }
          return c;
      }
  
      static long[][] exp(long mat[][], long b, long mod){
          if(b==0){
              int n = mat.length;
              long res[][] = new long[n][n];
              for(int i=0;i<n;i++){
                  res[i][i] = 1;
              }
              return res;
          }
          long half[][] = exp(mat, b/2, mod);
          long res[][] = matrixMult(half, half, mod);
          if(b%2==1){
              res = matrixMult(res, mat, mod);
          }
          return res;
      }
  
      static void countPrimeFactors(int num, int a[], HashMap<Integer,Integer> pos){
          for(int i=2;i*i<num;i++){
              if(num%i==0){
                  int y = pos.get(i);
                  while(num%i==0){
                      a[y]++;
                      num/=i;
                  }
              }
          }
          if(num>1){
              int y = pos.get(num);
              a[y]++;
          }
      }
  
      static void assignAnc(ArrayList<Integer> ar[], int depth[], int sz[], int par[][] ,int curr, int parent, int d){
          depth[curr] = d;
          sz[curr] = 1;
          par[curr][0] = parent;
          for(int v:ar[curr]){
              if(parent==v)
                  continue;
              assignAnc(ar, depth, sz, par, v, curr, d+1);
              sz[curr] += sz[v];
          }
      }
  
      static int findLCA(int a, int b, int par[][], int depth[]){
          if(depth[a]>depth[b]){
              a = a^b;
              b = a^b;
              a = a^b;
          }
          int diff = depth[b] - depth[a];
          for(int i=19;i>=0;i--){
              if((diff&(1<<i))>0){
                  b = par[b][i];
              }
          }
          if(a==b)
              return a;
          for(int i=19;i>=0;i--){
              if(par[b][i]!=par[a][i]){
                  b = par[b][i];
                  a = par[a][i];
              }
          }
          return par[a][0];
      }
  
      static void formArrayForBinaryLifting(int n, int par[][]){
          for(int j=1;j<20;j++){
              for(int i=0;i<n;i++){
                  if(par[i][j-1]==-1)
                      continue;
                  par[i][j] = par[par[i][j-1]][j-1];
              }
          }
      }
  
      static long lcm(int a, int b){
          return a*b/gcd(a,b);
      }
  
      static class Pair1 {
          long a;
          long b;
          
          Pair1(long a, long b) {
              this.a = a;
              this.b = b;
          }
      }
  
      static class Pair implements Comparable<Pair> {
          int a;
          int b;
          // int c;
          
          Pair(int a, int b) {
              this.a = a;
              this.b = b;
              // this.c = c;
          }
   
          public int compareTo(Pair p) {
              // if(c!=p.c)
              return a-p.a;
              // return b-p.b;
          }
      }
  
      static class Pair2 implements Comparable<Pair2> {
          int a;
          int b;
          int c;
          
          Pair2(int a, int b, int c) {
              this.a = a;
              this.b = b;
              this.c = c;
          }
   
          public int compareTo(Pair2 p) {
              return a-p.a;
          }
      }
  
      static boolean isPrime(int n) { 
          if (n <= 1) 
              return false; 
          if (n <= 3) 
              return true; 
          if (n % 2 == 0 ||  n % 3 == 0) 
              return false; 
          for (int i = 5; i * i <= n; i = i + 6) 
              if (n % i == 0 || n % (i + 2) == 0) 
                  return false; 
          return true; 
      } 
  
      static long gcd(long a, long b) {
          if (b == 0)
              return a;
          return gcd(b, a % b);
      }
  
      static long fast_pow(long base, long n, long M) {
          if (n == 0)
              return 1;
          if (n == 1)
              return base % M;
          long halfn = fast_pow(base, n / 2, M);
          if (n % 2 == 0)
              return (halfn * halfn) % M;
          else
              return (((halfn * halfn) % M) * base) % M;
      }
  
      static long modInverse(long n, long M) {
          return fast_pow(n, M - 2, M);
      }
  
      static class InputReader {
          public BufferedReader reader;
          public StringTokenizer tokenizer;
  
          public InputReader(InputStream stream) {
              reader = new BufferedReader(new InputStreamReader(stream), 9992768);
              tokenizer = null;
          }
  
          public String next() {
              while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                  try {
                      tokenizer = new StringTokenizer(reader.readLine());
                  } catch (IOException e) {
                      throw new RuntimeException(e);
                  }
              }
              return tokenizer.nextToken();
          }
  
          public int nextInt() {
              return Integer.parseInt(next());
          }
  
          public long nextLong() {
              return Long.parseLong(next());
          }
      }
  }