#include <stdio.h>
#define NMax 301

long n, m, x;
long a[NMax][NMax];
long sum[NMax][NMax];

void citire();
void rez();
int main()
{
	citire();
	rez();
	return 0;
}
void rez()
{
	FILE *g = fopen( "teren.out", "wt" );
	long i, j;

	for (i=1; i<=n; i++)
		for (j=1; j<=m; j++)
			  sum[i][j] = sum[i-1][j] + sum[i][j-1] + a[i][j] - sum[i-1][j-1];

	for (i=n; i>0; i--)
		 for ( j=m; j>0; j--)
			  if ( sum[i][j] <= x )
			  {
				 fprintf ( g, "%ld\n", (i*j) );
				 return;
			  }
}

void citire()
{
	long i, j;
	FILE *f = fopen( "teren.in", "rt" );
	fscanf( f, "%ld %ld %ld", &n, &m, &x );

	for (i=1; i<=n; i++)
		 for (j=1; j<=m; j++)
			  fscanf( f, "%ld", &a[i][j] );
}