// #define LOCAL
#define _USE_MATH_DEFINES
#include <array>
#include <cassert>
#include <cstdio>
#include <cstring>
#include <iostream>
#include <iomanip>
#include <string>
#include <sstream>
#include <vector>
#include <queue>
#include <stack>
#include <list>
#include <set>
#include <map>
#include <unordered_set>
#include <unordered_map>
#include <algorithm>
#include <complex>
#include <cmath>
#include <numeric>
#include <bitset>
#include <functional>
#include <random>
#include <ctime>

using namespace std;

template <typename A, typename B>
ostream& operator <<(ostream& out, const pair<A, B>& a) {
  out << "(" << a.first << "," << a.second << ")";
  return out;
}
template <typename T, size_t N>
ostream& operator <<(ostream& out, const array<T, N>& a) {
  out << "["; bool first = true;
  for (auto& v : a) { out << (first ? "" : ", "); out << v; first = 0;} out << "]";
  return out;
}
template <typename T>
ostream& operator <<(ostream& out, const vector<T>& a) {
  out << "["; bool first = true;
  for (auto v : a) { out << (first ? "" : ", "); out << v; first = 0;} out << "]";
  return out;
}
template <typename T, class Cmp>
ostream& operator <<(ostream& out, const set<T, Cmp>& a) {
  out << "{"; bool first = true;
  for (auto& v : a) { out << (first ? "" : ", "); out << v; first = 0;} out << "}";
  return out;
}
template <typename U, typename T, class Cmp>
ostream& operator <<(ostream& out, const map<U, T, Cmp>& a) {
  out << "{"; bool first = true;
  for (auto& p : a) { out << (first ? "" : ", "); out << p.first << ":" << p.second; first = 0;} out << "}";
  return out;
}
#ifdef LOCAL
#define trace(...) __f(#__VA_ARGS__, __VA_ARGS__)
#else
#define trace(...) 42
#endif
template <typename Arg1>
void __f(const char* name, Arg1&& arg1){
  cerr << name << ": " << arg1 << endl;
}
template <typename Arg1, typename... Args>
void __f(const char* names, Arg1&& arg1, Args&&... args){
  const char* comma = strchr(names + 1, ',');
  cerr.write(names, comma - names) << ": " << arg1 << " |";
  __f(comma + 1, args...);
}

template <class T> auto vect(const T& v, int n) { return vector<T>(n, v); }
template <class T, class... D> auto vect(const T& v, int n, D... m) {
  return vector<decltype(vect(v, m...))>(n, vect(v, m...));
}

typedef long long int64;
typedef pair<int, int> ii;
#define SZ(x) (int)((x).size())
template <typename T> static constexpr T inf = numeric_limits<T>::max() / 2;
const int MOD = 1e9 + 7;
// const int MOD = 998244353;
mt19937 mrand(random_device{}());
int rnd(int x) { return mrand() % x; }
// mt19937_64 mrand(random_device{}());
// int64 rnd(int64 x) { return mrand() % x; }
template <class T> void out(const vector<T>& a) { for (int i = 0; i < SZ(a); ++i) cout << a[i] << " \n"[i + 1 == SZ(a)]; }
template <class T> bool ckmin(T& a, const T& b) { return b < a ? a = b, 1 : 0; }
template <class T> bool ckmax(T& a, const T& b) { return a < b ? a = b, 1 : 0; }
template <class T> void dedup(vector<T>& v) { sort(v.begin(), v.end()); v.erase(unique(v.begin(), v.end()), v.end()); }
void add(int& x, int y) { x += y; if (x >= MOD) x -= MOD; }

struct fast_ios {
  fast_ios() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cout << fixed << setprecision(10);
  };
} fast_ios_;

int main() {
  int n, m, len;
  cin >> n >> m >> len;
  auto b = vect<int>(0, n, m);
  for (int i = 0; i < n; ++i) {
    for (int j = 0; j < m; ++j) {
      cin >> b[i][j];
      --b[i][j];
    }
  }

  int nn = n * m + len;
  vector<vector<ii>> a(nn);
  auto add_edge =
    [&](int x, int y, int z) {
      // trace(x, y, z);
      a[x].push_back({y, z});
    };

  for (int k = 0; k + 1 < len; ++k) {
    add_edge(k, k + 1, 0);
  }
  for (int i = 0; i < n; ++i) {
    for (int j = 0; j < m; ++j) {
      int x = len + i * m + j;
      add_edge(x, b[i][j], 0);
      add_edge(b[i][j], x, 0);
      if (i + 1 < n) {
        int y = len + (i + 1) * m + j;
        if (b[i][j] < b[i + 1][j]) {
          add_edge(x, y, 1);
        } else if (a[i][j] > a[i + 1][j]) {
          add_edge(y, x, 1);
        }
      }
      if (j + 1 < m) {
        int y = len + i * m + (j + 1);
        if (b[i][j] < b[i][j + 1]) {
          add_edge(x, y, 1);
        } else if (b[i][j] > b[i][j + 1]) {
          add_edge(y, x, 1);
        }
      }
    }
  }

  vector<int> d(nn, -inf<int>);
  vector<bool> visit(nn);
  d[0] = 0;
  visit[0] = true;
  vector<int> Q = {0};
  while (!Q.empty()) {
    int u = Q.back();
    Q.pop_back();
    visit[u] = false;
    for (auto& [v, w] : a[u]) {
      trace(u, v, w, d[u], d[v]);
      if (d[v] < d[u] + w) {
        d[v] = d[u] + w;
        if (!visit[v]) {
          visit[v] = true;
          Q.push_back(v);
        }
      }
    }
  }

  trace(d);
  cout << d[len - 1] + 1 << '\n';
  return 0;
}