#include <bits/stdc++.h>
using namespace std;

int main() {
	int n,m,k; cin >> n >> m >> k;
    vector <vector <int>> v(n,vector <int> (m));
    vector <vector <int>> dp(n,vector <int> (m));
    vector <vector <pair <int,int>>> parent(n,vector <pair<int,int>> (m,{0,0}));
    for(int i = 0;i < n; i++){
        for(int j = 0; j < n; j++){
            cin >> v[i][j];
            if(i > 0 && j > 0){
                dp[i][j] = min(dp[i-1][j],dp[i][j-1]) + v[i][j];
                if(dp[i-1][j] < dp[i][j-1]){
                    parent[i][j] = {i-1,j};
                }else{
                    parent[i][j] = {i,j-1};
                }
            }else{
                if(i == 0 && j != 0){
                    dp[i][j] = v[i][j] + dp[i][j-1];
                    parent[i][j] = {i,j-1};

                }
                if(i != 0 && j == 0){
                    dp[i][j] = v[i][j] + dp[i-1][j];
                    parent[i][j] = {i-1,j};

                }
                dp[0][0] = v[0][0];
                parent[0][0] = {0,0};
            }
        }
    }
    vector <int> ans;
    pair <int,int> par = {n-1,m-1};
    while(par.first > 0 || par.second > 0){
        cerr << par.first << ' ' << par.second << '\n';
        ans.push_back(v[par.first][par.second]);
        par = parent[par.first][par.second];
    }
    ans.push_back(v[0][0]);
    sort(ans.begin(),ans.end());
    int sum = 0;
    for(int i = ans.size()-1; i > 0; i--){
        while(k > 0){
            ans[i] /= 2;
            k--;
            if(ans[i] < ans[i-1]){
                break;
            }
        }
        sum += ans[i];
    }


    cout << sum;
}