#include<cstdio>
#include<cstdlib>
#include<iostream>
using namespace std;

struct peanut {
    int x, y, value;
};
int m, n, k, t;
int mov(int now, peanut p[])
{
    int diff;
    diff = abs(p[now - 1].x - p[now].x) + abs(p[now - 1].y - p[now].y);
    return diff;
}

void sort(peanut p[])
{
    for (int i = 1; i < t; i++)
        for (int j = i + 1; j <= t; j++)
            if (p[i].value < p[j].value) {
                swap(p[i].x, p[j].x);
                swap(p[i].y, p[j].y);
                swap(p[i].value, p[j].value);
            }
}

int main()
{
    cin >> m >> n >> k;
    t = 0;
    struct peanut p[(m + 1) * (n + 1)];
    int i, j;

    for (i = 1; i <= m; i++)
        for (j = 1; j <= n; j++) {
            cin >> p[++t].value;
            p[t].x = j;
            p[t].y = i;

            if (p[t].value == 0) {
                t--;
            }
        }

    sort(p);
    int now = 1, total = 0;
    p[0].x = p[1].x;
    p[0].y = 0;
    p[0].value = 0;

    while ((k > 0) && ((k - mov(now, p)) > p[now].y)) {
        k -= mov(now, p);
        k--;
        total += p[now].value;
        now++;
    }

    cout << total;
    return 0;
}
/*#include<stdio.h>
struct fuck{
    int val;
    int x,y;
};
int main(void)
{
    int row,col,time;
    scanf("%d %d %d",&row,&col,&time);
    fuck pnt[row*col];
    int num=0;
    for(int i=1;i<=row;++i)
        for(int j=1;j<=col;++j){
            int tmp;
            scanf("%d",&tmp);
            if(tmp>0){
                 pnt[num].val=tmp;
                 pnt[num].x=i;
                 pnt[num++].y=j;
            }
        }
    int total=0, max,p,q,p2=0,q2;
    while(1){
        max=0;
        for(int i=1;i<num;++i)
                if(max<pnt[i].val){
                    max=pnt[i].val;
                    p=pnt[i].x;
                    q=pnt[i].y;
                    pnt[i].val=0;
                }
        int tmp= p>p2?p-p2:p2-p;
        if(p2==0) q2=q;
        time-=(1+(q>q2?q-q2:q2-q)+tmp);
        if(time>=tmp&&max!=0){
            total+=max;
            p2=p,q2=q;
        }
        else{
            printf("%d\n",total);
            return 0;
        }
    }
}*/