#include<stdio.h>
FILE *fin,*fout;
int a[301][301],x,nr,i,j,l,c,nr1,max,t,n,m;
int main(){
fin=fopen("teren.in","r");
fout=fopen("teren.out","w");
fscanf(fin,"%d %d %d",&n,&m,&x);
for(i=1;i<=n;i++){
	for(j=1;j<=m;j++){
		fscanf(fin,"%d",&a[i][j]);
		a[i][j]+=a[i][j-1];
	}
}
for(i=1;i<=n;i++){
	for(j=1;j<=m;j++){
		for(l=n-i;l>=0;l--){
			for(c=m-j;c>=0;c--){
				nr1=0;
				for(t=i;t<=i+l;t++){
					nr1+=a[t][j+c]-a[t][j-1];
				}
				if(nr1<=x){break;}
			}
			if(nr1<=x){break;}
		}
		if((l+1)*(c+1)>max){max=(l+1)*(c+1);}
	}
}
fprintf(fout,"%d",max);
return 0;}