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.util.HashSet;
  import java.util.HashMap;
  import java.util.ArrayList;
  import java.util.Stack;
  import java.util.Collections;
  import java.util.Arrays;
  import java.util.Scanner;
  import java.io.BufferedReader;
  import java.io.IOException;
  import java.io.InputStreamReader;
  import java.util.StringTokenizer;
  
  public class D1619{
      
      static class FastReader {
          BufferedReader br;
          StringTokenizer st;
   
          public FastReader()
          {
              br = new BufferedReader(
                  new InputStreamReader(System.in));
          }
   
          String next()
          {
              while (st == null || !st.hasMoreElements()) {
                  try {
                      st = new StringTokenizer(br.readLine());
                  }
                  catch (IOException e) {
                      e.printStackTrace();
                  }
              }
              return st.nextToken();
          }
   
          int nextInt() { return Integer.parseInt(next()); }
   
          long nextLong() { return Long.parseLong(next()); }
   
          double nextDouble()
          {
              return Double.parseDouble(next());
          }
   
          String nextLine()
          {
              String str = "";
              try {
                  str = br.readLine();
              }
              catch (IOException e) {
                  e.printStackTrace();
              }
              return str;
          }
      }
      
      public static int[] sort(int[] arr,int low,int high){
          int[] sortedArray;
          if (low==high) {
              sortedArray=new int[]{arr[low]};
              return sortedArray;
          }
          int mid=(low+high)/2;
          int[] arr1=sort(arr,low,mid);
          int[] arr2=sort(arr,mid+1,high);
  
          sortedArray=merge(arr1,low,mid,arr2,mid+1,high);
          return sortedArray;
  
      }
  
      public static int[] merge(int[] arr1,int low1,int high1,int[] arr2,int low2,int high2){
  
          int size1=high1-low1+1;
          int size2=high2-low2+1;
          
          int[] arr=new int[size1+size2];
          int pointer=0;
          low1=0;low2=0;
          while (low1<size1 && low2<size2){
              if (arr1[low1] <= arr2[low2]) {
                  arr[pointer++]=arr1[low1++];
              }
              else{
                  arr[pointer++]=arr2[low2++];
              }
  
          }
  
          while(low1<size1) arr[pointer++]=arr1[low1++];
          while(low2<size2) arr[pointer++]=arr2[low2++];
          return arr;
      }
      
      public static boolean good(int[][] arr,int m,int n,long key){
          HashSet<Integer> hs=new HashSet<>();
          boolean two=false;
          for(int i=0;i<n;i++){
              boolean found=false;
              for(int j=0;j<m;j++){
                  if (arr[j][i] >= key) {
                    found=true;
                    if (hs.contains(j)) two=true;
                    else hs.add(j);
                  } 
              }
              if (!found) return false;
          }
          if (!two) return false;
          else return true;
      }
      
   
      public static void main(String[] args){
          FastReader sc=new FastReader();
          int t=sc.nextInt();
          while(t-- > 0){
              int m=sc.nextInt();
              int n=sc.nextInt();
              int[][] shops=new int[m][n];
              long l=1000000001;
              for(int i=0;i<m;i++) {
                  for(int j=0;j<n;j++){
                      shops[i][j]=sc.nextInt();
                      l=Math.min(l,shops[i][j]) ;                   
                  }
              }
              long r=1000000001;
              while(r > l+1){
                long mid=(l+r)/2;
                boolean flag=good(shops,m,n,mid);
                if (flag) l=mid;
                else r=mid;
              }
              System.out.println(l);
          }
      }   
  }
  