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#include <bits/stdc++.h>
using namespace std;
struct Query {
int x, y, u, v, id;
};
const int D[4][2] = {{-1,0},{1,0},{0,-1},{0,1}};
const int N = 307;
const int Q = 2e4+7;
int n, q, a[N][N];
Query ques[Q];
bool inside(int x, int y) {
return x >= 1 && x <= n && y >= 1 && y <= n;
}
namespace sub1 {
int dist[N][N];
int dijkstra(int su, int sv, int tu, int tv) {
priority_queue<pair<int, pair<int,int>>> heap;
memset(dist, 0, sizeof dist);
dist[su][sv] = a[su][sv];
heap.emplace(dist[su][sv], make_pair(su,sv));
while (!heap.empty()) {
int u = heap.top().second.first;
int v = heap.top().second.second;
int w = heap.top().first;
heap.pop();
if (w != dist[u][v]) continue;
if (u == tu && v == tv)
return dist[u][v];
for (int i = 0; i < 4; ++i) {
int x = u + D[i][0];
int y = v + D[i][1];
if (inside(x,y)) {
if (dist[x][y] < min(dist[u][v], a[x][y])) {
dist[x][y] = min(dist[u][v], a[x][y]);
heap.emplace(dist[x][y], make_pair(x,y));
}
}
}
}
return dist[tu][tv];
}
void solve() {
for (int i = 1; i <= q; ++i) {
cout << dijkstra(ques[i].x, ques[i].y, ques[i].u, ques[i].v) << '\n';
}
}
}
int main() {
cin.tie(nullptr)->sync_with_stdio(false);
#ifdef NHPHUCQT
freopen("demo.inp", "r", stdin);
freopen("demo.out", "w", stdout);
#else
freopen("matrice2.in", "r", stdin);
freopen("matrice2.out", "w", stdout);
#endif
cin >> n >> q;
for (int i = 1; i <= n; ++i)
for (int j = 1; j <= n; ++j) {
cin >> a[i][j];
}
for (int i = 1; i <= q; ++i) {
cin >> ques[i].x >> ques[i].y >> ques[i].u >> ques[i].v;
ques[i].id = i;
}
sub1::solve();
return 0;
}