#include <iostream>
#include <fstream>
using namespace std;
ifstream fin  ("teren.in");
ofstream fout ("teren.out");
int n, m, x, k, sol;
int s[301][301];
int scrt, st, dr;
int main (){
     fin>>n>>m>>x;
     for(int i=1; i<=n; i++)
          for(int j=1; j<=m; j++){
               fin>>k;
               s[i][j]=s[i-1][j] + k;
          }
     for(int i=1; i<=n; i++)
          for(int j=i; j<=n; j++){
               st=1;
               scrt=0;
               for(int dr=1; dr<=m; dr++){
                    scrt+=(s[j][dr] - s[i-1][dr]);
                    while(scrt > x){
                         scrt-=(s[j][st] - s[i-1][st]);
                         st++;
                    }
                    sol=max(sol, (dr-st+1)*(j-i+1));
               }
          }
     fout<<sol;
     return 0;
}