// dinamit.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include <iostream>
#include <climits>
#include <cmath>
#include<algorithm>
#define ll long long 
using namespace std;
ll n, m, k;
ll dp[41][41][41];
ll x[41][41];
int main()
{
    cin >> n >> m >> k;
    for (int i = 1; i <= n; ++i)
        for (int j = 1; j <= m; ++j)cin >> x[i][j];
    for (int i = 1; i <= n; ++i)
    {
        ll mini = LLONG_MAX;
        for (int l = 0; l <= k; ++l)
        {
            for (int o = 0; o <= l; ++o)
            {
                ll a = (pow(2, l - o));
                mini = min(mini, dp[i - 1][1][o] + x[i][i] / a);
            }
            dp[i][1][l] = mini;
        }
    }
    for (int j = 1; j <= n; ++j)
    {
        ll mini = LLONG_MAX;
        for (int l = 0; l <= k; ++l)
        {
            for (int o = 0; o <= l; ++o)
            {
                ll a = (pow(2, l - o));
                mini = min(mini, dp[1][j-1][o] + x[1][j] / a);
            }
            dp[1][j][l] = mini;
        }
    }
    for (int i = 2; i <= n; ++i)
    {
        for (int j = 2; j <= m; ++j)
        {
            for (int l = 0; l <= k; ++l)
            {
                ll mini =LLONG_MAX;
                for (int o = 0; o <= l; ++o)
                {
                    ll a = (pow(2, l - o));
                    mini = min(mini,min(dp[i-1][j][o], dp[i][j-1][o]) + x[i][j] /a );
                }
                dp[i][j][l] = mini;
            }
        }
    }
    ll ans = LLONG_MAX;

   for (int l = 0; l <= k; ++l)
        ans = min(dp[n][n][l], ans);
   cout << ans;
 /*for (int i = 1; i <= n; ++i)
    {
        for (int j = 1; j <= m; ++j)
        {
            for (int l = 0; l <= k; ++l)
            {
                cout << dp[i][j][l] << " ";
            }
            cout << " ";
        }
        cout << "\n";
    }
  */
    return 0;
}

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