#include<bits/stdc++.h>
using namespace std;
int a,b,k,mei,o;
struct mm{
    int zh,x,y;  
}n[1000005];
bool cmp(mm x,mm y){
	return x.zh>y.zh;
}
int main(){
    cin>>a>>b>>k;
    for(int i=1;i<=a;i++){
        for(int j=1;j<=b;j++){
            cin>>mei;
            if(mei>=1)n[++o].zh=mei,n[o].x=i,n[o].y=j;
        }        
    }
    sort(n+1,n+1+o,cmp);
    int x=0,y=n[1].y;
    int s=0,sum=0;
    for(int i=1;i<=o;i++){
    	if(s+abs(n[i].x-x)+abs(n[i].y-y)+1+n[i].x>k){
    		cout<<sum;
    		return 0;
    	}
    	sum+=n[i].zh;
    	s+=abs(n[i].x-x)+abs(n[i].y-y)+1;
    	x=n[i].x,y=n[i].y;
    }
    cout<<sum;
    return 0;
}