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: # from itertools import accumulate
  import os
  import sys
  from io import BytesIO, IOBase
  BUFSIZE = 8192
  class FastIO(IOBase):
      newlines = 0
      def __init__(self, file):
          self._fd = file.fileno()
          self.buffer = BytesIO()
          self.writable = 'x' in file.mode or 'r' not in file.mode
          self.write = self.buffer.write if self.writable else None
      def read(self):
          while True:
              b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
              if not b:break
              ptr = self.buffer.tell()
              self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
          self.newlines = 0
          return self.buffer.read()
      def readline(self):
          while self.newlines == 0:
              b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
              self.newlines = b.count(b'\n') + (not b)
              ptr = self.buffer.tell()
              self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
          self.newlines -= 1
          return self.buffer.readline()
      def flush(self):
          if self.writable:
              os.write(self._fd, self.buffer.getvalue())
              self.buffer.truncate(0), self.buffer.seek(0)
  class IOWrapper(IOBase):
      def __init__(self, file):
          self.buffer = FastIO(file)
          self.flush = self.buffer.flush
          self.writable = self.buffer.writable
          self.write = lambda s: self.buffer.write(s.encode('ascii'))
          self.read = lambda: self.buffer.read().decode('ascii')
          self.readline = lambda: self.buffer.readline().decode('ascii')
  sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
  input = lambda: sys.stdin.readline().rstrip('\r\n')
  
  
  def transpose(arr):
      r, c = len(arr), len(arr[0])
      ans = [[arr[i][j] for i in range(r)] for j in range(c)]
      return ans
  
  # def max_arr(arr):
  #     x = [*accumulate(arr, func = max)]
  #     y = [*accumulate(arr[::-1], func = max)][::-1]
  #     ans = [0 for i in range(len(arr))]
  
  #     ans[0] = y[1]
  #     for i in range(1, len(arr) - 1):
  #         ans[i] = max(x[i - 1], y[i + 1])
  #     ans[-1] = x[-2]
  #     return ans
  
  class SegmentTree:
      def __init__(self, a, fx, val):
          self.n = len(a)
          self.val = val
          self.fx = fx
          self.tree = [val] * self.n * 2
          for i in range(self.n): self.tree[i + self.n] = a[i]
          for i in range(self.n - 1, 0, -1): self.tree[i] = fx(self.tree[i << 1], self.tree[i << 1 | 1])
      def modify(self, p, value):
          p, self.tree[p] = self.n + p, value
          while p > 1:
              self.tree[p>>1] = self.fx(self.tree[p], self.tree[p ^ 1])
              p >>= 1
      def query(self, l, r):
          l, r, ans = l + self.n, r + self.n, self.val
          while l < r:
              if l & 1:ans, l = self.fx(ans, self.tree[l]), l + 1
              if r & 1:ans, r = self.fx(ans, self.tree[r - 1]), r - 1
              l, r = l >> 1, r >> 1
          return ans
      def get(self, p):
          return self.tree[p + n]
  
  
  
  def solve(num_shops, num_friends, fsjoytable, sfjoytable):
      foptimal_shop_index = [max(enumerate(fsjoytable[idx_friend]), key = lambda x: x[1])[0] for idx_friend in range(num_friends)]
      if len(foptimal_shop_index) == len(set(foptimal_shop_index)):
          # # print(foptimal_shop_index)
          # fsjoytable_new = [sfjoytable[idx_shop] for idx_shop in foptimal_shop_index]
          # sfjoytable_new = transpose(fsjoytable_new)
          # print(fsjoytable_new)
          # # print(fsjoytable_new)
          # fsmaxjoytable = [max_arr(row) for row in sfjoytable_new]
          # minimumjoy = [min(fsmaxjoytable[i][shop] for i in range(num_friends)) for shop in range(num_friends)]
          # return minimumjoy
  
          maxjoy = [sfjoytable[idx_shop][idx_friend] for idx_friend, idx_shop in enumerate(foptimal_shop_index)]
          st = SegmentTree(maxjoy, min, 10 ** 12)
          final_ans = []
          for idx_shop, shop in enumerate(sfjoytable):
              ishop = sorted(enumerate(shop), key = lambda x : x[1], reverse = True)
              fid_1, fid_2 = ishop[0][0], ishop[1][0]
              qp1, qp2 = min(fid_1, fid_2), max(fid_1, fid_2)   
              val = min(st.query(0, qp1), st.query(qp1 + 1, qp2), st.query(qp2 + 1, num_friends))
              final_ans.append(min(val, ishop[0][1], ishop[1][1]))
          return max(final_ans)
      else:
          joys = [sfjoytable[foptimal_shop_index[idx_friend]][idx_friend] for idx_friend in range(num_friends)]
          return min(joys)
  
  
  
  for _ in range(int(input())):
      input()
      m, n = map(int, input().split())
      joytable = [list(map(int, input().split())) for _ in range(m)]
      val = solve(m, n, transpose(joytable), joytable)
      print(val)