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.IOException;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.PrintWriter;
  import java.util.InputMismatchException;
  import java.util.*;
  
  public class NewYearProblem {
      static InputReader inputReader=new InputReader(System.in);
      static void solve()
      {
          int m=inputReader.nextInt();
          int n= inputReader.nextInt();
          int matrix[][]=new int[m][n];
          int max=Integer.MIN_VALUE;
          for (int i=0;i<m;i++)
          {
              for (int j=0;j<n;j++)
              {
                  matrix[i][j]=inputReader.nextInt();
                  max=Math.max(max,matrix[i][j]);
              }
          }
          int res=-1;
          int low=1;
          int high=max;
          while (low<=high)
          {
              int mid=low+(high-low)/2;
              if (check(matrix,mid,m,n))
              {
                  res=mid;
                  low=mid+1;
              }
              else
              {
                  high=mid-1;
              }
          }
          out.println(res);
      }
      static boolean check(int matrix[][],int val,int m,int n)
      {
          boolean found2=false;
          boolean found1=false;
          HashSet<Integer>hashSet=new HashSet<>();
          for (int i=0;i<m;i++) {
              int count=0;
              for (int j = 0; j < n; j++) {
                  if (matrix[i][j] >= val)
                  {
                      hashSet.add(j);
                      count++;
                  }
                  if (count>=2)
                  {
                      found2=true;
                  }
              }
          }
          if (hashSet.size()==n)
          {
              found1=true;
          }
          return found1&&found2;
  
      }
      static void add(long ele,TreeMap<Long,Integer>treeMap)
      {
          treeMap.put(ele,treeMap.getOrDefault(ele,0)+1);
      }
     static  void remove(long ele,TreeMap<Long,Integer>treeMap)
      {
          treeMap.put(ele,treeMap.get(ele)-1);
          if (treeMap.get(ele)==0)
          {
              treeMap.remove(ele);
          }
      }
      static PrintWriter out=new PrintWriter((System.out));
      public static void main(String args[])throws IOException
      {
          int t=inputReader.nextInt();
          while (t-->0) {
              solve();
          }
              out.close();
      }
      static class InputReader {
  
          private InputStream stream;
          private byte[] buf = new byte[8192];
          private int curChar, snumChars;
          private SpaceCharFilter filter;
  
          public InputReader(InputStream stream) {
              this.stream = stream;
          }
  
          public int snext() {
              if (snumChars == -1)
                  throw new InputMismatchException();
              if (curChar >= snumChars) {
                  curChar = 0;
                  try {
                      snumChars = stream.read(buf);
                  } catch (IOException e) {
                      throw new InputMismatchException();
                  }
                  if (snumChars <= 0)
                      return -1;
              }
              return buf[curChar++];
          }
  
          public int nextInt() {
              int c = snext();
              while (isSpaceChar(c))
                  c = snext();
              int sgn = 1;
              if (c == '-') {
                  sgn = -1;
                  c = snext();
              }
              int res = 0;
              do {
                  if (c < '0' || c > '9')
                      throw new InputMismatchException();
                  res *= 10;
                  res += c - '0';
                  c = snext();
              } while (!isSpaceChar(c));
              return res * sgn;
          }
  
          public long nextLong() {
              int c = snext();
              while (isSpaceChar(c))
                  c = snext();
              int sgn = 1;
              if (c == '-') {
                  sgn = -1;
                  c = snext();
              }
              long res = 0;
              do {
                  if (c < '0' || c > '9')
                      throw new InputMismatchException();
                  res *= 10;
                  res += c - '0';
                  c = snext();
              } while (!isSpaceChar(c));
              return res * sgn;
          }
  
          public int[] nextIntArray(int n) {
              int a[] = new int[n];
              for (int i = 0; i < n; i++)
                  a[i] = nextInt();
              return a;
          }
  
          public String readString() {
              int c = snext();
              while (isSpaceChar(c))
                  c = snext();
              StringBuilder res = new StringBuilder();
              do {
                  res.appendCodePoint(c);
                  c = snext();
              } while (!isSpaceChar(c));
              return res.toString();
          }
  
          public boolean isSpaceChar(int c) {
              if (filter != null)
                  return filter.isSpaceChar(c);
              return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
          }
  
          public interface SpaceCharFilter {
              public boolean isSpaceChar(int ch);
          }
      }
  }
  