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#include <bits/stdc++.h>
using namespace std;
typedef pair<int, int> pii;
const int maxn = 310;
const int maxv = 9e4+10;
int n, q;
int tab[maxn][maxn];
int pai[maxv], peso[maxv], nivel[maxv], edge[maxv];
vector<pii> V[1000001];
int linha[] = {-1, 1, 0, 0};
int coluna[] = {0, 0, -1, 1};
void init(void)
{
for (int i = 1; i <= n*n; i++)
pai[i] = i, peso[i] = 1;
}
int Find(int x)
{
if (pai[x] == x) return x;
return Find(pai[x]);
}
void Join(int x, int y, int tt)
{
x = Find(x), y = Find(y);
if (x == y) return;
if (peso[x] < peso[y]) swap(x, y);
pai[y] = x, peso[x] += peso[y], edge[y] = tt;
}
int dfs(int u)
{
if (u == Find(u)) return 0;
if (nivel[u] != -1) return nivel[u];
nivel[u] = dfs(pai[u])+1;
return nivel[u];
}
int get(int u, int v)
{
int mx = 0;
while (u != v)
{
if (nivel[u] > nivel[v])
{
mx = max(mx, edge[u]);
u = pai[u];
}
else
{
mx = max(mx, edge[v]);
v = pai[v];
}
}
return mx;
}
int main(void)
{
scanf("%d %d", &n, &q);
for (int i = 1; i <= n; i++)
{
for (int j = 1; j <= n; j++)
{
scanf("%d", &tab[i][j]);
V[tab[i][j]].push_back({i, j});
}
}
init();
int tt = 0;
for (int T = 1000000; T >= 1; T--)
{
++tt;
for (auto pp: V[T])
{
int x = pp.first, y = pp.second;
for (int i = 0; i < 4; i++)
{
int a = x+linha[i], b = y+coluna[i];
if (a < 1 || a > n || b < 1 || b > n || tab[a][b] < T) continue;
Join((x-1)*n + y, (a-1)*n + b, tt);
}
}
}
memset(nivel, -1, sizeof nivel);
for (int i = 1; i <= n*n; i++)
if (nivel[i] == -1)
dfs(i);
for (int i = 1; i <= q; i++)
{
int x1, y1, x2, y2;
scanf("%d %d %d %d", &x1, &y1, &x2, &y2);
int mx = get((x1-1)*n+y1, (x2-1)*n+y2);
printf("%d\n", 1000000-mx+1);
}
}