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 sys, collections, math, bisect, heapq, random, functools,io,os,copy
  input = sys.stdin.readline
  out = sys.stdout.flush
  def rep():
      a = list(map(int,input().split()))
      return a
  
  def sep():
      a = list(input().split())
      return a
  
  
  class UnionFind:
      def __init__(self, x) -> None:
          self.uf = [-1] * x
  
      def find(self, x):
          r = x
          while self.uf[x] >= 0:
              x = self.uf[x]
  
          while r != x:
              self.uf[r], r = x, self.uf[r]
          return x
  
      def union(self, x, y):
          ux, uy = self.find(x), self.find(y)
          if ux == uy:
              return
          if self.uf[ux] >= self.uf[uy]:
              self.uf[uy] += self.uf[ux]
              self.uf[ux] = uy
          else:
              self.uf[ux] += self.uf[uy]
              self.uf[uy] = ux
          return
  
      def __print__(self):
          return self.uf
  
  
  def spfa(x,g,n):
      dis = [float('inf') for i in range(n)]
      dis[x] = 0
      state = [False for i in range(n)]
      state[x] = True
      queue = collections.deque()
      queue.append(x)
      while queue:
          cur = queue.popleft()
          state[cur] = False
          for next_ in g[cur]:
              if dis[next_] > dis[cur] + 1:
                  dis[next_] = dis[cur] + 1
                  if state[next_] == False:
                      state[next_] = True
                      queue.append(next_)
      return dis
  
  
  def gcd(x,y):
      if y == 0:
          return x
      return gcd(y,x % y)
  
  def valid(x,mat):
      m,n = len(mat),len(mat[0])
      cnt = [0 for i in range(m)]
      flag = [0 for i in range(n)]
      for i in range(m):
          for j in range(n):
              if mat[i][j] >= x:
                  cnt[i] += 1
                  flag[j] = 1
      return True if max(cnt) > 1 and sum(flag) == n else 0
  
  
  
  def solve():
      t = input()
      m,n = map(int,input().split())
      matrix = [list(map(int,input().split())) for i in range(m)]
      l,r = float('inf'),float('inf')
  
      pre = collections.defaultdict(list)
  
      for j in range(n):
          temp = -float('inf')
          for i in range(m):
              temp = max(temp,matrix[i][j])
              l = min(l,matrix[i][j])
          r = min(r,temp)
  
  
  
      while l <= r:
          mid = l + (r - l) // 2
          if valid(mid,matrix):
              l = mid + 1
          else:
              r = mid - 1
      print(l - 1)
  
  
  if __name__ == '__main__':
      for i in range(int(input())):
          solve()