#include<bits/stdc++.h>
using namespace std;
int k=0,a[30][30],n,m,s=2,t,sum;
struct ad{
	int x,y;
	int sl;
}b[770];
bool px(ad n1,ad n2){
	return n1.sl>n2.sl;
}
int main(){
	cin>>n>>m>>t;
	for(int i=0;i<n;i++){
		for(int j=0;j<m;j++){
			cin>>a[i][j];
			if(a[i][j]!=0) b[k].sl=a[i][j],b[k].x=i,b[k].y=j,k++;
		} 
	}
	sort(b,b+k,px);
	if(t<2*b[0].x+1){
		cout<<0;
		return 0;
	}
	int p=1,q=1;
	for(int i=0;i<k;i++){
		s=s+1+abs(p-b[i].x)+abs(q-b[i].y);
		p=b[i].x,q=b[i].y;
		if(s+b[i].x<t) sum+=b[i].sl;
		else break;
	}
	cout<<sum;
	return 0;
	
}