#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <cmath>
#include <map>
#include <set>
#define FOR(var,bound) for(int var = 0; var < bound; var++)
#define FORB(var,lb,ub) for (int var = lb; var < ub; var++)
#define FORR(var,bound) for(int var = bound-1; var >= 0; var--)
using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<vector<int>> vvi;
typedef pair<int, int> pii;
int rectangle(int R, int C, int H, int W, int Q[3001][3001]) {
int res = 10000000;
for (int i = 0; i + H <= R; i++) {
for (int j = 0; j + W <= C; j++) {
vector<int> vals;
for (int k = 0; k < H; k++) {
for (int l = 0; l < W; l++) {
vals.push_back(Q[i + k][j + l]);
}
}
sort(vals.begin(), vals.end());
res = min(res, vals[H * W / 2]);
}
}
return res;
}
#ifdef LOCAL_TEST
int grid[3001][3001];
signed main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
int r, c, h, w;
cin >> r >> c >> h >> w;
FOR(i, r) {
FOR(j, c) {
cin >> grid[i][j];
}
}
cout << rectangle(r, c, h, w, grid) << endl;
}
#endif
