description: The Hat is a game of speedy explanation/guessing words (similar to Alias). It's fun. Try it! In this problem, we are talking about a variant of the game when the players are sitting at the table and everyone plays individually (i.e. not teams, but individual gamers play).
  
  n people gathered in a room with m tables (n ≥ 2m). They want to play the Hat k times. Thus, k games will be played at each table. Each player will play in k games.
  
  To do this, they are distributed among the tables for each game. During each game, one player plays at exactly one table. A player can play at different tables.
  
  Players want to have the most "fair" schedule of games. For this reason, they are looking for a schedule (table distribution for each game) such that:
  
    * At any table in each game there are either ⌊n/m⌋ people or ⌈n/m⌉ people (that is, either n/m rounded down, or n/m rounded up). Different numbers of people can play different games at the same table.
    * Let's calculate for each player the value b_i — the number of times the i-th player played at a table with ⌈n/m⌉ persons (n/m rounded up). Any two values of b_imust differ by no more than 1. In other words, for any two players i and j, it must be true |b_i - b_j| ≤ 1. 
  
  
  
  For example, if n=5, m=2 and k=2, then at the request of the first item either two players or three players should play at each table. Consider the following schedules:
  
    * First game: 1, 2, 3 are played at the first table, and 4, 5 at the second one. The second game: at the first table they play 5, 1, and at the second — 2, 3, 4. This schedule is not "fair" since b_2=2 (the second player played twice at a big table) and b_5=0 (the fifth player did not play at a big table).
    * First game: 1, 2, 3 are played at the first table, and 4, 5 at the second one. The second game: at the first table they play 4, 5, 2, and at the second one — 1, 3. This schedule is "fair": b=[1,2,1,1,1] (any two values of b_i differ by no more than 1). 
  
  
  
  Find any "fair" game schedule for n people if they play on the m tables of k games.
  
  Input
  
  The first line of the input contains an integer t (1 ≤ t ≤ 10^4) — the number of test cases in the test.
  
  Each test case consists of one line that contains three integers n, m and k (2 ≤ n ≤ 2⋅10^5, 1 ≤ m ≤ ⌊n/2⌋, 1 ≤ k ≤ 10^5) — the number of people, tables and games, respectively.
  
  It is guaranteed that the sum of nk (n multiplied by k) over all test cases does not exceed 2⋅10^5.
  
  Output
  
  For each test case print a required schedule — a sequence of k blocks of m lines. Each block corresponds to one game, a line in a block corresponds to one table. In each line print the number of players at the table and the indices of the players (numbers from 1 to n) who should play at this table.
  
  If there are several required schedules, then output any of them. We can show that a valid solution always exists.
  
  You can output additional blank lines to separate responses to different sets of inputs.
  
  Example
  
  Input
  
  
  3
  5 2 2
  8 3 1
  2 1 3
  
  
  Output
  
  
  3 1 2 3
  2 4 5
  3 4 5 2
  2 1 3
  
  2 6 2
  3 3 5 1
  3 4 7 8
  
  2 2 1
  2 2 1
  2 2 1
solution: import java.util.*;
  import java.io.*;
  
  public class Main {
      static FastScanner sc = new FastScanner(System.in);
      static PrintWriter pw = new PrintWriter(System.out);
      static StringBuilder sb = new StringBuilder();
      static long mod = (long) 1e9 + 7;
      
      public static void main(String[] args) throws Exception {
          int n = sc.nextInt();
          for(int i = 0; i < n; i++) solve();
          pw.flush();
      }
  
      public static void solve() {
          int N = sc.nextInt();
          int M = sc.nextInt();
          int K = sc.nextInt();
          int start = 0;
          int next = 0;
          int table = N/M;
          for(int i = 0; i < K; i++){
              int rem = N%M;
              for(int j = 0; j < M; j++){
                  if(rem > 0){
                      sb.append(table+1).append(" ");
                      for(int jj = 0; jj < table+1; jj++){
                          sb.append(start+1).append(" ");
                          start++;
                          start %= N;
                          next++;
                          next %= N;
                      }
                      rem--;
                  }else{
                      sb.append(table).append(" ");
                      for(int jj = 0; jj < table; jj++){
                          sb.append(next+1).append(" ");
                          next++;
                          next %= N;
                      }
                  }
                  pw.println(sb.toString());
                  sb.setLength(0);
              }
              next = start;
          }
          pw.println();
      }
      
      static class GeekInteger {
          public static void save_sort(int[] array) {
              shuffle(array);
              Arrays.sort(array);
          }
  
          public static int[] shuffle(int[] array) {
              int n = array.length;
              Random random = new Random();
              for (int i = 0, j; i < n; i++) {
                  j = i + random.nextInt(n - i);
                  int randomElement = array[j];
                  array[j] = array[i];
                  array[i] = randomElement;
              }
              return array;
          }
  
          public static void save_sort(long[] array) {
              shuffle(array);
              Arrays.sort(array);
          }
  
          public static long[] shuffle(long[] array) {
              int n = array.length;
              Random random = new Random();
              for (int i = 0, j; i < n; i++) {
                  j = i + random.nextInt(n - i);
                  long randomElement = array[j];
                  array[j] = array[i];
                  array[i] = randomElement;
              }
              return array;
          }
  
      }
  }
  
  class FastScanner {
      private BufferedReader reader = null;
      private StringTokenizer tokenizer = null;
  
      public FastScanner(InputStream in) {
          reader = new BufferedReader(new InputStreamReader(in));
          tokenizer = null;
      }
  
      public FastScanner(FileReader in) {
          reader = new BufferedReader(in);
          tokenizer = null;
      }
  
      public String next() {
          if (tokenizer == null || !tokenizer.hasMoreTokens()) {
              try {
                  tokenizer = new StringTokenizer(reader.readLine());
              } catch (IOException e) {
                  throw new RuntimeException(e);
              }
          }
          return tokenizer.nextToken();
      }
  
      public String nextLine() {
          if (tokenizer == null || !tokenizer.hasMoreTokens()) {
              try {
                  return reader.readLine();
              } catch (IOException e) {
                  throw new RuntimeException(e);
              }
          }
          return tokenizer.nextToken("\n");
      }
  
      public long nextLong() {
          return Long.parseLong(next());
      }
  
      public int nextInt() {
          return Integer.parseInt(next());
      }
  
      public double nextDouble() {
          return Double.parseDouble(next());
      }
  
      public String[] nextArray(int n) {
          String[] a = new String[n];
          for (int i = 0; i < n; i++)
              a[i] = next();
          return a;
      }
  
      public int[] nextIntArray(int n) {
          int[] a = new int[n];
          for (int i = 0; i < n; i++)
              a[i] = nextInt();
          return a;
      }
  
      public long[] nextLongArray(int n) {
          long[] a = new long[n];
          for (int i = 0; i < n; i++)
              a[i] = nextLong();
          return a;
      }
  }
  