#include <fstream>

using namespace std;

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

int n,m,i,j,x,a[305][305],i1,i2,s[305][305];

int main()
{
    fin >> n >> m >> x;
    for (i=1; i<=n; i++)
        for (j=1; j<=m; j++)
        {
            fin >> s[i][j];
            s[i][j] += s[i-1][j] + s[i][j-1] - s[i-1][j-1];
        }
    int maxim = 0;
    for (i1=1; i1<=n; i1++)
        for (i2=i1; i2<=n; i2++)
        {
            int st = 1;
            for (int dr=1; dr<=m; dr++)
            {
                while (s[i2][dr]-s[i2][st-1]-s[i1-1][dr]+s[i1-1][st-1] > x && st <= dr)
                    st++;
                maxim = max(maxim, (i2-i1+1)*(dr-st+1));
            }
        }
    fout << maxim;
    return 0;
}