#include <fstream>
using namespace std;
ifstream fin("teren.in");
ofstream fout("teren.out");
int n,i,j,p,k,m,sum,i1,i2,j1,j2,maxim,v[310][310],s[1000][1000];
int main () {
    fin>>n>>p>>k;
    for (i=1;i<=n;i++) {
        for (j=1;j<=m;j++) {
            fin>>v[i][j];
            s[i][j]=s[i-1][j]+s[i][j-1]-s[i-1][j-1]+v[i][j];
        }
    }
    for (i=1;i<=n;i++) {
        for (j=1;j<=n;j++) {
            for (m=1;m<=n;m++) {
                i1=i;
                i2=i+m-1;
                j1=j-m+1;
                j2=j;
                if (j1>=1) {
                    sum=s[i2][j2]-s[i2][i1-1]-s[i1-1][j2]+s[i1-1][j1-1];
                    if (sum<=k && m>maxim)
                        maxim=m;
                }
            }
        }
    }
    fout<<maxim*maxim;
}