#include <fstream>
using namespace std;

#define FOR for (int i=1;i<=N;++i) for (int j=1;j<=N;++j)
#define For(x,y) for (int i=(x);i<=(y);++i)

#define Nmax 511
#define Lgmax 50

int A[Nmax][Nmax],N,M;
int Rmq[Lgmax][Nmax][Nmax];

int Lg2[Nmax];

int Query(int x,int y,int lat)
{
	int l = Lg2[lat],smax = 0;
	
	smax = max(Rmq[l][x][y], Rmq[l][x - (1<<l) + lat][y]);
	
	if( max(Rmq[l][x][y - (1<<l) + lat], Rmq[l][x - (1<<l) + lat][y - (1<<l) + lat]) > smax)
		smax = max(Rmq[l][x][y - (1<<l) + lat], Rmq[l][x - (1<<l) + lat][y - (1<<l) + lat]);
	
	return smax;
}

void Make()
{
	for(int k = 1; (1<<k)<=N; ++k)
		for(int i=1;i<=N - (1<<k) + 1;++i)
			for(int j=1;j<=N - (1<<k) + 1;++j) 
			{
				int l = 1<<(k-1);
				
				Rmq[k][i][j] = max(Rmq[k-1][i][j], Rmq[k-1][i+l][j]);
				
				if(	max(Rmq[k-1][i][j+l], Rmq[k-1][i+l][j+l]) > Rmq[k][i][j])
					Rmq[k][i][j] = max(Rmq[k-1][i][j+l], Rmq[k-1][i+l][j+l]);
			}
}

int main(void)
{
	ifstream F("plantatie.in");
	ofstream G("plantatie.out");

	F>>N>>M;
	FOR F>>A[i][j];
	
	FOR Rmq[0][i][j]=A[i][j];
	For(2,N) Lg2[i]=Lg2[i/2]+1;
	
	Make();
	
	int x,y,l;
	
	For(1,M) F>>x>>y>>l,G<<Query(x,y,l)<<'\n';
	
	F.close();
	G.close();
}