#include<stdio.h>
#include <queue>
using namespace std;
int n,m,x,A,S[301][301],i,j,rez,l1,l2,suma,nre,a,v,cnt;
char buff[701];
int get_nr()
{
	int neg;
	neg=1;
	int nr=0;
	for(int i=cnt;i<m;i++)
	{
		if(buff[i]=='-') neg=-1;
		else if(buff[i]>='0' && buff[i]<='9') nr=nr*10+(buff[i]-'0');
		else if(buff[i]==' ') {cnt=i+1;return nr*neg;};
	}
	return nr*neg;
}
queue <int> Q;
int main()
{
	freopen("teren.in","r",stdin);
	freopen("teren.out","w",stdout);
	scanf("%d%d%d",&n,&m,&x);
	for (i=1;i<=n;i++)
	{
		scanf("%s",&buff);
		for (j=1;j<=m;j++){A=get_nr();  S[i][j]=S[i-1][j]+A;}
	}
	rez=0;
	for (l1=1;l1<=n;l1++)
		for (l2=l1;l2<=n;l2++)
		{
			while (!Q.empty()) Q.pop();
			nre=suma=0;
			for (i=1;i<=m;i++)
			{
				v=S[l2][i]-S[l1-1][i];
				Q.push(v);
				nre++;
				suma=suma+v;
				while (suma>x) {a=Q.front(); Q.pop(); suma=suma-a; nre--;}
				if (nre*(l2-l1+1)>rez) rez=nre*(l2-l1+1);
			}
		}
	printf("%d\n",rez);
	return 0;
}