#include<cstdio>
#include<algorithm>
const int MAXN=20+5+5;
int m,n,k,a[MAXN][MAXN],sum,fx,fy,ex,ey,tm,ans;
struct dire{
int x,y,sum;
}N[MAXN*MAXN];
bool cmp(dire a,dire b){
return a.sum>b.sum;
}
int main(){
scanf("%d %d %d",&n,&m,&k);
for(int i=1;i<=n;i++){
for(int j=1;j<=m;j++){
scanf("%d",&a[i][j]);
if(a[i][j]>0){
sum++;
N[sum].x=i;
N[sum].y=j;
N[sum].sum=a[i][j];
}
}
}
std::sort(N+1,N+sum+1,cmp);
fx=1,fy=N[1].y,k--;/*
for(int i=1;i<=sum;i++)
printf("%d ",N[i].sum);*/
//printf("\n");
for(int i=1;i<=sum;i++){
tm=0;
ex=N[i].x;
ey=N[i].y;
tm=std::abs(fx-ey)+std::abs(fy-ey);
k--;
k-=tm;
if(k>=ex){
ans+=a[ex][ey];
fx=ex,fy=ey;
}else{
printf("%d",ans);
return 0;
}
}
printf("%d",ans);
return 0;
}