#include <bits/stdc++.h>

using namespace std;

#define ll long long
#define ull unsigned ll
#define vec vector
#define flist forward_list
#define um unordered_map
#define us unordered_set
#define prioq priority_queue
#define all(x) x.begin(), x.end()
#define pb push_back
#define pf push_front
#define fi first
#define se second
#define ld long double
#define point complex<ld>
#define pll pair<ll, ll>
#define tll tuple<ll, ll, ll>
#define ass assign
#define fun function

#define LL_MAX LLONG_MAX
#define LL_MIN LLONG_MIN
#define ULL_MAX ULLONG_MAX
#define LD_MAX LDBL_MAX
#define LD_MIN LDBL_MIN

#define nl '\n'

#define vv(type, name, n, ...) vector<vector<type>> name(n, vector<type>(__VA_ARGS__))
#define vvv(type, name, n, m, ...) \
    vector<vector<vector<type>>> name(n, vector<vector<type>>(m, vector<type>(__VA_ARGS__)))

// https://trap.jp/post/1224/
#define rep1(n) for(ll i=0; i<(ll)(n); ++i)
#define rep2(i,n) for(ll i=0; i<(ll)(n); ++i)
#define rep3(i,a,b) for(ll i=(ll)(a); i<(ll)(b); ++i)
#define rep4(i,a,b,c) for(ll i=(ll)(a); i<(ll)(b); i+=(ll)(c))
#define cut4(a,b,c,d,e,...) e
#define rep(...) cut4(__VA_ARGS__,rep4,rep3,rep2,rep1)(__VA_ARGS__)
#define rep1e(n) for(ll i=1; i<=(ll)(n); ++i)
#define rep2e(i,n) for(ll i=1; i<=(ll)(n); ++i)
#define rep3e(i,a,b) for(ll i=(ll)(a); i<=(ll)(b); ++i)
#define rep4e(i,a,b,c) for(ll i=(ll)(a); i<=(ll)(b); i+=(ll)(c))
#define repe(...) cut4(__VA_ARGS__,rep4e,rep3e,rep2e,rep1e)(__VA_ARGS__)
#define per1(n) for(ll i=(ll)(n)-1; i>=0; --i)
#define per2(i,n) for(ll i=(ll)(n)-1; i>=0; --i)
#define per3(i,a,b) for(ll i=(ll)(a)-1; i>=(ll)(b); --i)
#define per4(i,a,b,c) for(ll i=(ll)(a)-1; i>=(ll)(b); i-=(ll)(c))
#define per(...) cut4(__VA_ARGS__,per4,per3,per2,per1)(__VA_ARGS__)
#define per1e(n) for(ll i=(ll)(n); i>=1; --i)
#define per2e(i,n) for(ll i=(ll)(n); i>=1; --i)
#define per3e(i,a,b) for(ll i=(ll)(a); i>=(ll)(b); --i)
#define per4e(i,a,b,c) for(ll i=(ll)(a); i>=(ll)(b); i-=(ll)(c))
#define pere(...) cut4(__VA_ARGS__,per4e,per3e,per2e,per1e)(__VA_ARGS__)
#define rep_subset(i,s) for(ll i=0;i!=-1;i=i==(s)?-1:(i|~(s))+1&(s))
#define per_subset(i,s) for(ll i=(s);i!=-1;i=i==0?-1:i-1&(s))
// #define forit(v) for (auto it = v.begin(); it != v.end(); it++)
// #define forit2(it, v) for (auto it = v.begin(); it != v.end(); it++)
// #define forrit(v) for (auto it = v.rbegin(); it != v.rend(); it++)
// #define forrit2(it, v) for (auto it = v.rbegin(); it != v.rend(); it++)

// #ifdef i_am_noob
#define bug(...) cerr << "#" << __LINE__ << ' ' << #__VA_ARGS__ << "- ", _do(__VA_ARGS__)
template<typename T> void _do(vector<vector<T>> x){cerr << "\n"; for(auto i: x) {for(auto j : i) {cerr << j << ' ';} cerr << "\n";}}
template<typename T> void _do(vector<T> x){for(auto i: x) cerr << i << ' ';cerr << "\n";}
template<typename T> void _do(set<T> x){for(auto i: x) cerr << i << ' ';cerr << "\n";}
template<typename T> void _do(unordered_set<T> x){for(auto i: x) cerr << i << ' ';cerr << "\n";}
template<typename T> void _do(T && x) {cerr << x << endl;}
template<typename T, typename ...S> void _do(T && x, S&&...y) {cerr << x << ", "; _do(y...);}
// #else
// #define bug(...) 777771449
// #endif
template<class T, class S> bool mkmin(T& a, const initializer_list<S>& b)
{S m = *min_element(all(b)); if(m<a){a=m;return 1;}return 0;}
template<class T, class S> bool mkmax(T& a, const initializer_list<S>& b)
{S m = *max_element(all(b)); if(m>a){a=m;return 1;}return 0;}
template<class T, class S> bool mkmin(T& a, const S& b){if(b<a){a=b;return 1;}return 0;}
template<class T, class S> bool mkmax(T& a, const S& b){if(b>a){a=b;return 1;}return 0;}

const ll MOD = 1e9 + 7;
const ll INF = (1ll << 59);

const string FILENAME = "matrice2";
ifstream fin(FILENAME + ".in");
ofstream fout(FILENAME + ".out");

#define cin fin
#define cout fout

ll dx[]={-1,0,1,0}, dy[]={0,1,0,-1};

class Dsu
{
public:

	vec<ll> queriesAns, parent, size;
	vec<set<ll>> ends;
	
	void build(ll n, vec<pll>& queries)
	{
		parent.ass(n,-1);
		size.ass(n,1);
		ends.resize(n);
		queriesAns.resize(queries.size());
		
		rep(queries.size())
		{
			ends[queries[i].fi].insert(i);
			ends[queries[i].se].insert(i);
		}
	}
	ll find(ll a)
	{
		if(parent[a]==-1) return a;
		return parent[a] = find(parent[a]);
	}
	void unite(ll a, ll b, ll val)
	{
		a = find(a), b = find(b);
		if(a==b)return;
		if(size[a]<size[b])swap(a,b);
		
		for(auto e : ends[b])
		{
			if(ends[a].find(e) != ends[a].end())
			{
				queriesAns[e] = val;
				ends[a].erase(e);
			}
			else
			{
				ends[a].insert(e);
			}
		}
		ends[b].clear(); // DISABLE MAYBE IN CASE OF TLE
		
		size[a] += size[b];
		parent[b] = a;
	}
};

int main()
{
	ll n, q;
	cin >> n >> q;
	
	Dsu dsu;
	vec<tll> squares(n*n);
	vec<pll> queries(q);
	vec<vec<bool>> mat(n, vec<bool>(n, 0));
	rep(n) rep(j, n)
	{
		ll val;
		cin >> val;
		squares[i*n+j] = {val, i, j};
	}
	
	sort(all(squares),[](const auto& a, const auto& b)
	{
		return get<0>(a) > get<0>(b);
	});

	rep(q)
	{
		ll x1, y1, x2, y2;
		cin >> x1 >> y1 >> x2 >> y2;
		x1--,y1--,x2--,y2--;
		queries[i] = {x1*n+y1, x2*n+y2};
	}
	
	dsu.build(n*n, queries);
	fun<bool(ll,ll)>oob([&](ll x, ll y)
	{
		if(0<=x&&x<n&&0<=y&&y<n && mat[x][y] == 1) return 0;
		return 1;
	});
	
	rep(squares.size())
	{
		ll val = get<0>(squares[i]);
		
		while(i < squares.size() && get<0>(squares[i]) == val)
		{
			ll x = get<1>(squares[i]), y = get<2>(squares[i]);
			mat[x][y] = 1;
			rep(d, 4)
			{
				ll nx = x+dx[d], ny = y+dy[d];
				if(!oob(nx, ny))
				{
					dsu.unite(x*n+y, nx*n+ny, val);
				}
			}
			i++;
		}
		i--;
	}
	
	for(auto e : dsu.queriesAns) cout << e << nl;
	
    return 0;
}