description: Vlad has n friends, for each of whom he wants to buy one gift for the New Year.
  
  There are m shops in the city, in each of which he can buy a gift for any of his friends. If the j-th friend (1 ≤ j ≤ n) receives a gift bought in the shop with the number i (1 ≤ i ≤ m), then the friend receives p_{ij} units of joy. The rectangular table p_{ij} is given in the input.
  
  Vlad has time to visit at most n-1 shops (where n is the number of friends). He chooses which shops he will visit and for which friends he will buy gifts in each of them.
  
  Let the j-th friend receive a_j units of joy from Vlad's gift. Let's find the value α=min\\{a_1, a_2, ..., a_n\}. Vlad's goal is to buy gifts so that the value of α is as large as possible. In other words, Vlad wants to maximize the minimum of the joys of his friends.
  
  For example, let m = 2, n = 2. Let the joy from the gifts that we can buy in the first shop: p_{11} = 1, p_{12}=2, in the second shop: p_{21} = 3, p_{22}=4.
  
  Then it is enough for Vlad to go only to the second shop and buy a gift for the first friend, bringing joy 3, and for the second — bringing joy 4. In this case, the value α will be equal to min\{3, 4\} = 3
  
  Help Vlad choose gifts for his friends so that the value of α is as high as possible. Please note that each friend must receive one gift. Vlad can visit at most n-1 shops (where n is the number of friends). In the shop, he can buy any number of gifts.
  
  Input
  
  The first line of the input contains an integer t (1 ≤ t ≤ 10^4) — the number of test cases in the input.
  
  An empty line is written before each test case. Then there is a line containing integers m and n (2 ≤ n, 2 ≤ n ⋅ m ≤ 10^5) separated by a space — the number of shops and the number of friends, where n ⋅ m is the product of n and m.
  
  Then m lines follow, each containing n numbers. The number in the i-th row of the j-th column p_{ij} (1 ≤ p_{ij} ≤ 10^9) is the joy of the product intended for friend number j in shop number i.
  
  It is guaranteed that the sum of the values n ⋅ m over all test cases in the test does not exceed 10^5.
  
  Output
  
  Print t lines, each line must contain the answer to the corresponding test case — the maximum possible value of α, where α is the minimum of the joys from a gift for all of Vlad's friends.
  
  Example
  
  Input
  
  
  5
  
  2 2
  1 2
  3 4
  
  4 3
  1 3 1
  3 1 1
  1 2 2
  1 1 3
  
  2 3
  5 3 4
  2 5 1
  
  4 2
  7 9
  8 1
  9 6
  10 8
  
  2 4
  6 5 2 1
  7 9 7 2
  
  
  Output
  
  
  3
  2
  4
  8
  2
solution: import java.io.*;
  import java.util.*;
  
  public class D {
      private boolean isOk(long[][] g, int m, int n, long min) {
          int atMost = Math.min(n - 1, m);
          int cnt = 0;
          Set<Integer> shops = new HashSet<>();
  
          for(int i = 0; i < n; i++) {
              Set<Integer> set = new HashSet<>();
              for(int j = 0; j < m; j++) {
                  if(g[j][i] >= min) {
                      set.add(j);
                  }
              }
              if(set.isEmpty()) return false;
  
              boolean needMore = true;
              for(int x : set) {
                  if(shops.contains(x)) {
                      needMore = false;
                      break;
                  }
              }
              if(needMore) {
                  shops.addAll(set);
                  cnt++;
              }
          }
  
          return cnt <= Math.min(n - 1, m);
      }
      void go() {
          //Reader.next();
          int m = Reader.nextInt();
          int n = Reader.nextInt();
          long[][] g = new long[m][n];
          //Writer.println(m + " " + n);
          long lo = Long.MAX_VALUE;
          long hi = 0;
          for(int i = 0; i < m; i++) {
              for(int j = 0; j < n; j++) {
                  g[i][j] = Reader.nextLong();
                  lo = Math.min(lo, g[i][j]);
                  hi = Math.max(hi, g[i][j]);
              }
          }
          //System.out.println(lo + " " + hi);
          long ans = 0;
          while(lo <= hi) {
              long mid = lo + hi >> 1;
  
              if(isOk(g, m, n, mid)) {
                  ans = mid;
                  lo = mid + 1;
              } else {
                  hi = mid - 1;
              }
          }
  
          Writer.println(ans);
      }
      void solve() {
          for(int T = Reader.nextInt(); T > 0; T--) go();
      }
      void run() throws Exception {
          Reader.init(System.in);
          Writer.init(System.out);
          solve();
          Writer.close();
      }
  
      public static void main(String[] args) throws Exception {
          new D().run();
      }
  
      public static class Reader {
          public static StringTokenizer st;
          public static BufferedReader br;
  
          public static void init(InputStream in) {
              br = new BufferedReader(new InputStreamReader(in));
              st = new StringTokenizer("");
          }
  
          public static String next() {
              while(!st.hasMoreTokens()) {
                  try {
                      st = new StringTokenizer(br.readLine());
                  } catch (IOException e) {
                      throw new InputMismatchException();
                  }
              }
              return st.nextToken();
          }
  
          public static int nextInt() {
              return Integer.parseInt(next());
          }
  
          public static long nextLong() {
              return Long.parseLong(next());
          }
  
          public static double nextDouble() {
              return Double.parseDouble(next());
          }
      }
  
      public static class Writer {
          public static PrintWriter pw;
  
          public static void init(OutputStream os) {
              pw = new PrintWriter(new BufferedOutputStream(os));
          }
  
          public static void print(String s) {
              pw.print(s);
          }
  
          public static void print(char c) {
              pw.print(c);
          }
  
          public static void print(int x) {
              pw.print(x);
          }
  
          public static void print(long x) {
              pw.print(x);
          }
  
          public static void println(String s) {
              pw.println(s);
          }
  
          public static void println(char c) {
              pw.println(c);
          }
  
          public static void println(int x) {
              pw.println(x);
          }
  
          public static void println(long x) {
              pw.println(x);
          }
  
          public static void close() {
              pw.close();
          }
      }
  }