#include <fstream>
using namespace std;
int minim (int n,int m,int p){
    if (n<=m&&n<=p)
        return n;
    if (m<=n&&m<=p)
        return m;
    return p;

}
int n,m,p,i,j,maxim,x,L[310][310],s[310][310];
int main (){
    ifstream fin  ("teren.in");
    ofstream fout("teren.out");
    fin>>n>>m>>p;
    for (i=1;i<=n;i++)
        for (j=1;j<=m;j++){
            fin>>x;
            L[i][j]=1+minim(L[i-1][j],L[i][j-1],L[i-1][j-1]);
            s[i][j]=s[i][j-1]+s[i-1][j]-s[i-1][j-1]+x;
            if (s[i][j]<=p&&L[i][j]*L[i][j]>maxim)
                maxim=L[i][j]*L[i][j];
        }
    fout<<maxim;
}