from collections import deque

N,M,K = map(int,input().split())
A = [list(map(int,input().split())) for i in range(N)]

if N + M - 1 <= K:
  ans = 10 ** 9
  print(ans)
  exit()

D = [(0,1),(0,-1),(-1,0),(1,0)]
l = 1
r = 10 ** 9 + 1
while r - l > 1:
  m = (l + r) // 2
  C = [[-1 for _ in range(M)] for _ in range(N)]
  if A[0][0] < m:
    C[0][0] = 1
  else:
    C[0][0] = 0
  dq = deque([(0,0)])
  while len(dq):
    u,v = dq.popleft()
    c = C[u][v]
    for dx,dy in D:
      if 0 <= u + dx < N and 0 <= v + dy < M:
        uu,vv = u + dx,v + dy
        if C[uu][vv] != -1:
          continue
        cc = c
        if A[uu][vv] < m:
          cc += 1
          C[uu][vv] = cc
          dq.append((uu,vv))
          continue
        C[uu][vv] = cc
        dq.appendleft((uu,vv))
  if C[-1][-1] <= K:
    l = m
  else:
    r = m
print(l)