#include <stdio.h>
#include <stdlib.h>

/* run this program using the console pauser or add your own getch, system("pause") or input loop */
    typedef struct hua
    {
	   int x;
	   int y;
	   int n;
	}FL;
	FL fl[400];
	int a[20][20];
	int jue (int a,int b,int c,int d)
	{
	   int x,y;
	   x=a-c;
	   y=b-d;
	   if(x<0)   x=-x;
	   if(y<0)   y=-y;
	   return x+y;
	}
int main(int argc, char *argv[]) {
    int m,n,k,i,j,count=0,t,time,sum=0;
    scanf("%d %d %d",&m,&n,&k);
    for(i=1;i<=m;i++)
        for(j=1;j<=n;j++)
        {
		    scanf("%d",&a[i][j]);
		    if(a[i][j]!=0)
		    {
			   fl[count].n=a[i][j];
			   fl[count].x=i;
			   fl[count].y=j;
			   count++; 
			} 
		}
	for(i=0;i<=count-2;i++)
	   for(j=i+1;j<=count-1;j++)
	       if(fl[i].n<fl[j].n)
	       {
		       t=fl[i].n;
			   fl[i].n=fl[j].n;
			   fl[j].n=t;
		       t=fl[i].x;
			   fl[i].x=fl[j].x;
			   fl[j].x=t;
			   t=fl[i].y;
			   fl[i].y=fl[j].y;
			   fl[j].y=t;
		   }
	time=fl[0].x+1;
	for(i=0;i<count;i++)
	{
	   if(time+fl[i].x<=k)
	   {
	      time=time+1+jue(fl[i+1].x,fl[i+1].y,fl[i].x,fl[i].y);
	      sum+=fl[i].n;
	   }
	   else
	      break;
	}   
	printf("%d",sum);	
	return 0;
}
/**************************************************************
	Problem: 2245
	User: admin
	Language: C
	Result: Accepted
	Time:52 ms
	Memory:1152 kb
****************************************************************/