#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>
using namespace std;
vector< vector<int> > mat;
vector< vector<int> > checked;
int N, M, K, num, maxim, mini, maxi;
void parc(int i, int j) {
    if (!checked[i][j] && mat[i][j] - mini <= K && maxi - mat[i][j] <= K) {
        ++num;
        checked[i][j] = 1;
        if (mat[i][j] < mini) {
            mini = mat[i][j];
        }
        if (mat[i][j] > maxi) {
            maxi = mat[i][j];
        }
        if (i < N - 1) {
            parc(i+1, j);
        }
        if (i > 0) {
            parc(i-1, j);
        }
        if (j < M - 1) {
           parc(i, j+1);
        }
        if (j > 0) {
           parc(i, j-1);
        }
    }
    if (num > maxim) {
        maxim = num;
    }
}
int main() {
    ifstream in("p2.in");
    ofstream out("p2.out");
    in >> N >> M >> K;
    mat.resize(N);
    checked.resize(N);
    maxim = 0;
    for (int i = 0; i < N; ++i) {
        mat[i].resize(M);
        checked[i].resize(M);
    }
    for (int i = 0; i < N; ++i) {
        for (int j = 0; j < M; ++j) {
            in >> mat[i][j];
            checked[i][j] = 0;
        }
    }
    for (int i = 0; i < N; ++i) {
        for (int j = 0; j < M; ++j) {
            mini = maxi = mat[i][j];
            parc(i, j);
            num = 0;
            /*checked.resize(N);
            for (int i = 0; i < N; ++i) {
                checked[i].resize(M);
            }*/
            for (int i = 0; i < N; ++i) {
                for (int j = 0; j < M; ++j) {
                    checked[i][j] = 0;
                }
            }
        }
    }
    out << maxim;
    return 0;
}