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.Arrays;
  
  public class D_1619 {
      static int shops = 0;
      static int friends = 0;
  
      public static void main(String[] args) throws FileNotFoundException {
  //        Scanner sc = new Scanner(new File("CodeForce_1619/test.txt"));
          FastScanner sc = new FastScanner(System.in);
          int cases = sc.nextInt();
          while (cases-- > 0){
              solve(sc);
          }
      }
  
      public static void solve(FastScanner sc){
          shops = sc.nextInt();
          friends = sc.nextInt();
  
          Pair[][] values = new Pair[friends][shops];
  
          for(int i = 0;i<shops;i++){
              for(int j = 0;j<friends;j++){
                  values[j][i] = new Pair(sc.nextInt(), i);        // checked read in to array
              }
          }
  
          int l = 1;
          int r = Integer.MAX_VALUE;
  
          for(int i = 0;i<friends;i++){
              Arrays.sort(values[i]);                 // checked sort
              if(values[i][0].x < r) r = values[i][0].x;   // checked bound
          }
  
          System.out.println(check(values,l,r));
      }
  
      public static int check(Pair[][] values,int l,int r){
          int tmp=0;
          while (l <= r){
              int mid = (l+r) / 2;
              if(check(values,mid)){
                  tmp = mid;
                  l=mid+1;
              } else{
                  r=mid-1;
              }
          }
          return tmp;
  
  //        if(r < l) return r;
  //        int mid = (l+r) / 2;
  //        if(check(values,mid)){
  //            l=mid;
  //            return check(values,l,r);
  //        } else{
  //            r = mid;
  //            return check(values,l,r);
  //        }
  
  
      }
  
      public static boolean check(Pair[][] values,int pij){
          int[] vis = new int[shops];
          for(int i = 0; i < friends;i++){
              for(int j = 0;j<shops;j++){
                  if(values[i][j].x >= pij) vis[values[i][j].y]++;
                  if(vis[values[i][j].y]>= 2) return true;
              }
          }
          return false;
      }
  
  }
  class Pair implements Comparable<Pair>{
      int x;
      int y;
      public  Pair(int x,int y){
          this.x = x;
          this.y = y;
      }
  
  
      @Override
      public int compareTo(Pair o) {
          return -(this.x - o.x);
      }
  }
  class FastScanner {
      static final int BufferSize = 1 << 20;
      static byte[] Buffer;
      static int index;
      static int total;
      static InputStream in;
  
      public FastScanner(InputStream is) {
          try {
              in = is;
              Buffer = new byte[BufferSize];
          } catch (Exception e) {
          }
      }
  
      private int read() {
          try {
              if (index >= total) {
                  index = 0;
                  total = in.read(Buffer);
                  if (total <= 0)
                      return -1;
              }
              return Buffer[index++];
          } catch (Exception | Error e) {
              System.err.println(e.getMessage());
              return 13 / 0;
          }
      }
  
      public String next() {
          int c;
          for (c = read(); c <= 32; c = read()) ;
          StringBuilder sb = new StringBuilder();
          for (; c > 32; c = read())
              sb.append((char) c);
          return sb.toString();
      }
  
      public int nextInt() {
          int c, value = 0;
          for (c = read(); c <= 32; c = read()) ;
          boolean neg = c == '-';
          if (c == '+' || c == '-')
              c = read();
          for (; c <= '9' && c >= '0'; c = read())
              value = (value << 3) + (value << 1) + (c & 15);
          return neg ? -value : value;
      }
  
      public int[] getIntArray(int size) {
          int[] arr = new int[size];
          for (int i = 0; i < size; ++i) arr[i] = nextInt();
          return arr;
      }
  
  }
  