from collections import deque
from collections.abc import Iterator


def neighbors4(r: int, c: int) -> Iterator[tuple[int, int]]:
    for dr, dc in [(-1, 0), (1, 0), (0, -1), (0, 1)]:
        nr = r + dr
        nc = c + dc
        if not (0 <= nr < N and 0 <= nc < M): continue
        yield nr, nc


INF = 1 << 60
N, M, K = map(int, input().split())
A = []
for _ in range(N):
    A.append(list(map(int, input().split())))


# 最小スコア m として到達可能か？(K 回だけマスを書き換え可能)
def bfs01(m: int) -> bool:
    g = [[INF] * M for _ in range(N)]
    q = deque([(0, 0)])
    g[0][0] = 1 if A[0][0] < m else 0

    while q:
        r, c = q.popleft()

        for nr, nc in neighbors4(r, c):
            if g[nr][nc] != INF: continue
            if A[nr][nc] < m:
                g[nr][nc] = g[r][c] + 1
                q.append((nr, nc))
            else:
                g[nr][nc] = g[r][c]
                q.appendleft((nr, nc))

    return g[N-1][M-1] <= K


lo = 1
hi = 10 ** 9
ans = lo
while lo <= hi:
    m = (lo + hi) // 2
    if bfs01(m):
        lo = m + 1
        ans = max(ans, m)
    else:
        hi = m - 1

print(ans)