#include <bits/stdc++.h>
using namespace std;
class InParser {
private:
FILE *fin;
char *buff;
int sp;
char read_ch() {
++sp;
if (sp == 4096) {
sp = 0;
fread(buff, 1, 4096, fin);
}
return buff[sp];
}
public:
InParser(const char* nume) {
fin = fopen(nume, "r");
buff = new char[4096]();
sp = 4095;
}
InParser& operator >> (int &n) {
char c;
while (!isdigit(c = read_ch()) && c != '-');
int sgn = 1;
if (c == '-') {
n = 0;
sgn = -1;
} else {
n = c - '0';
}
while (isdigit(c = read_ch())) {
n = 10 * n + c - '0';
}
n *= sgn;
return *this;
}
InParser& operator >> (long long &n) {
char c;
n = 0;
while (!isdigit(c = read_ch()) && c != '-');
long long sgn = 1;
if (c == '-') {
n = 0;
sgn = -1;
} else {
n = c - '0';
}
while (isdigit(c = read_ch())) {
n = 10 * n + c - '0';
}
n *= sgn;
return *this;
}
};
class OutParser {
private:
FILE *fout;
char *buff;
int sp;
void write_ch(char ch) {
if (sp == 50000) {
fwrite(buff, 1, 50000, fout);
sp = 0;
buff[sp++] = ch;
} else {
buff[sp++] = ch;
}
}
public:
OutParser(const char* name) {
fout = fopen(name, "w");
buff = new char[50000]();
sp = 0;
}
~OutParser() {
fwrite(buff, 1, sp, fout);
fclose(fout);
}
OutParser& operator << (int vu32) {
if(vu32 == -1){
write_ch('-');
write_ch('1');
} else if (vu32 <= 9) {
write_ch(vu32 + '0');
} else {
(*this) << (vu32 / 10);
write_ch(vu32 % 10 + '0');
}
return *this;
}
OutParser& operator << (long long vu64) {
if (vu64 <= 9) {
write_ch(vu64 + '0');
} else {
(*this) << (vu64 / 10);
write_ch(vu64 % 10 + '0');
}
return *this;
}
OutParser& operator << (char ch) {
write_ch(ch);
return *this;
}
OutParser& operator << (const char *ch) {
while (*ch) {
write_ch(*ch);
++ch;
}
return *this;
}
};
struct query{
int x1, y1, x2, y2, i;
int st, dr, m, ans;
bool operator<(const query &obj)const{
return m > obj.m;
}
};
struct elem{
int x, y, val;
bool operator< (const elem &obj)const{
return val >= obj.val;
}
};
const int nmax = 305, hmax = 1000005, dx[] = {1, -1, 0, 0}, dy[] = {0, 0, -1, 1};
int n, m, answered, c[nmax*nmax+5], rng[nmax*nmax+5], v[nmax][nmax], sol[20005];
vector<query> q;
vector<elem> e;
query make_query(int x1, int y1, int x2, int y2, int i, int st = 1, int dr = hmax, int m = hmax/2, int ans = 1)
{
query aux;
aux.x1 = x1;
aux.y1 = y1;
aux.x2 = x2;
aux.y2 = y2;
aux.i = i;
aux.st = st;
aux.dr = dr;
aux.m = m;
aux.ans = ans;
return aux;
}
elem make_elem(int x, int y, int val)
{
elem aux;
aux.x = x;
aux.y = y;
aux.val = val;
return aux;
}
int find(int x)
{
if(x == c[x])
return x;
c[x] = find(c[x]);
return c[x];
}
void unite(int x, int y)
{
if(rng[x] > rng[y])
c[y] = x;
else c[x] = y;
if(rng[x] == rng[y])
++rng[y];
}
bool check(int x, int y, int val)
{
return x > 0 && y > 0 && x <= n && y <= n && v[x][y] >= val;
}
int main()
{
InParser fin ("matrice2.in");
OutParser fout ("matrice2.out");
fin >> n >> m;
for (int i = 1; i <= n; ++i)
for (int j = 1; j <= n; ++j){
int x;
fin >> x;
v[i][j] = x;
e.push_back(make_elem(i, j, x));
}
sort(e.begin(), e.end());
for (int i = 1; i <= m; ++i){
int x1, y1, x2, y2;
fin >> x1 >> y1 >> x2 >> y2;
q.push_back(make_query(x1, y1, x2, y2, i));
}
while(answered < m){
for (int i = 1; i <= nmax*nmax; ++i){
c[i] = i;
rng[i] = 1;
}
sort(q.begin(), q.end());
/*for (vector<query>::iterator it = q.begin(); it != q.end(); ++it)
cout << it->x1 << " " << it->y1 << " " << it->m << "\n";
cout << "\n";
return 0;*/
int p = 0;
for (vector<elem>::iterator it = e.begin(); it != e.end(); ++it){
for (int i = 0; i < 4; ++i)
if(check(it->x+dx[i], it->y+dy[i], v[it->x][it->y]))
unite(find(it->x*nmax+it->y), find((it->x+dx[i])*nmax+it->y+dy[i]));
if(it+1 == e.end() || it->val > (it+1)->val){
int x = it->val;
while(q[p].m >= x && p < q.size()){
if(q[p].st > q[p].dr){
++p;
continue;
}
if(q[p].x1*nmax+q[p].y1 > nmax*nmax){
//cout << "" << "\n";
return 0;
}
if(find(q[p].x1*nmax+q[p].y1) == find(q[p].x2*nmax+q[p].y2)){
//if(q[p].i == 1)
//cout << x << "\n";
q[p].ans = x;
q[p].st = q[p].m+1;
}else
q[p].dr = q[p].m-1;
q[p].m = (q[p].st+q[p].dr)/2;
if(q[p].st > q[p].dr){
++answered;
sol[q[p].i] = q[p].ans;
}
++p;
}
}
}
}
for (int i = 1; i <= m; ++i)
fout << sol[i] << "\n";
return 0;
}