#include<bits/stdc++.h>
using namespace std;
int m,n,i,j,k=1,t,u,ans;
struct peanuts{
    int x,y,time,w;
};  peanuts p[1000001];
int a[1010][1010];
int main(){
    cin>>m>>n>>t;
    for(i=1;i<=m;i++)
       for(j=1;j<=n;j++){
          cin>>a[i][j];
             if(a[i][j]>0) {
             p[k].w=a[i][j];
             p[k].x=i;
             p[k].y=j;
             k++;
         }
      }
    for(i=1;i<k;i++)
       for(j=i+1;j<=k;j++)
          if(p[i].w<p[j].w)  swap(p[i],p[j]);
     for(i=1;i<=k;i++){
         u=p[i].x;
            if(i==1) p[i].time=p[i].x+1; 
              else   p[i].time=p[i-1].time+abs(p[i].x-p[i-1].x)+abs(p[i].y-p[i-1].y)+1;
                 if (p[i].time+u<=t) ans+=p[i].w;
     }
    cout<<ans;
    return 0;
}