#include <fstream>
using namespace std;
ifstream fin("teren.in");
ofstream fout("teren.out");
int n,m,i,j,x,a[303][303],i1,s[303][303],M,o,o1;
int main(){
    fin>>n>>m>>x;
    for(i=1;i<=n;i++){
        for(j=1;j<=m;j++){
            fin>>a[i][j];
        }
    }
    for(i=1;i<=n;i++){
        for(j=1;j<=m;j++){
            s[i][j]=s[i-1][j]+s[i][j-1]-s[i-1][j-1]+a[i][j];
        }
    }

    for(i=1;i<=n;i++){
        for(i1=i;i1<=n;i1++){
            o=1;
            for(o1=1;o1<=m;o1++){
                while(s[i1][o1]-s[i1][o-1]-s[i-1][o1]+s[i-1][o-1]>x&&o<o1){
                    o++;
                }
                if((i1-i+1)*(o1-o+1)>M){
                    M=(i1-i+1)*(o1-o+1);
                }
            }
        }
    }
    fout<<M;
    return 0;
}