ABC203D WA

// Problem: D - Pond
// Contest: AtCoder - AtCoder Beginner Contest 203（Sponsored by Panasonic）
// URL: https://atcoder.jp/contests/abc203/tasks/abc203_d
// Memory Limit: 1024 MB
// Time Limit: 2000 ms
//
// Powered by CP Editor (https://cpeditor.org)

#include <assert.h>
#include <bits/stdc++.h>
using namespace std;
#define dbg(...) logger(#__VA_ARGS__, __VA_ARGS__)
template <typename... Args> void logger(string vars, Args &&... values)
{
    cerr << vars << " = ";
    string delim = "";
    (..., (cerr << delim << values, delim = ", "));
    cerr << endl;
}

template <class T> inline auto vv(int m) { return vector<vector<T>>(m, vector<T>(m)); }
template <class T> inline auto vv(int m, int n) { return vector<vector<T>>(m, vector<T>(n)); }
template <class T, T init> inline auto vv(int m) { return vector<vector<T>>(m, vector<T>(m, init)); }
template <class T, T init> inline auto vv(int m, int n) { return vector<vector<T>>(m, vector<T>(n, init)); }

template <class T> using mpq = priority_queue<T, vector<T>, greater<T>>;
using ll = long long;
using pii = pair<int, int>;

int k, n;

int main(int argc, char **argv)
{
    cin >> n >> k;
    auto v = vv<int>(n);
    for (int i = 0; i < n; ++i)
        for (int j = 0; j < n; ++j)
            cin >> v[i][j];

    auto check = [&v](int x) {
        auto ps = vv<ll>(n + 1);
        for (int i = 0; i < n; ++i)
            for (int j = 0; j < n; ++j)
                ps[i + 1][j + 1] = ps[i + 1][j] + ps[i][j + 1] + (v[i][j] <= x ? 1 : 0) - ps[i][j];
        for (int i = k; i <= n; ++i)
            for (int j = k; j <= n; ++j)
                if (ps[i][j] - ps[i - k][j] - ps[i][j - k] + ps[i - k][j - k] >= k * k / 2 + 1)
                    return true;
        return false;
    };
    int lb = 0, ub = 1e9 + 3, cnt = ub - lb, step, it;
    while (cnt) {
        it = lb, step = cnt / 2, it += step;
        if (!check(it)) {
            lb = it + 1;
            cnt -= step + 1;
        } else
            cnt = step;
    }
    cerr << check(lb - 1) << endl;
    cout << lb << endl;
    return 0;
};