#include <fstream>
using namespace std;

ifstream fin ("teren.in");
ofstream fout("teren.out");

int n,m,X,i,j,x,y,a[303][303],z,maxim;

int main(){
    fin>>n>>m>>X;
    for (i=1;i<=n;i++)
        for (j=1;j<=m;j++){
            fin>>z;
            a[i][j]=z+a[i-1][j]+a[i][j-1]-a[i-1][j-1];
        }
    for (i=1;i<=n;i++)
        for (x=i;x<=n;x++){
            y=0;
            for (j=1;j<=m && y<=m;j++)
                for (y=j;y<=m && a[x][y]-a[x][j-1]-a[i-1][y]+a[i-1][j-1]<=X;y++)
                    maxim=max(maxim,(x-i+1)*(y-j+1));
        }
    fout<<maxim;
    fin.close();
    fout.close();
    return 0;
}