// Arhiva educationala - Arbori de intervale
var
	n, m, i, t, a, b : longint;
	v : array[1..400100] of longint;
	f, g : text;
	
function query   (nod, st, dr, a, b : longint) : longint;
var
	m1, m2, mij, t : longint;
begin
if (a <= st) and (dr <= b) then
	begin
	query := v[nod]; exit
	end;
mij := (st+dr) shr 1; 
t := nod shl 1;
if (a <= mij) then
	m1 := query (t, st, mij, a, b);
if (mij < b) then
	m2 := query (t + 1, mij+1, dr, a, b);
if (m1 >= m2) then query := m1 else query := m2;
end;

procedure update (nod, st, dr, poz, val : longint);
var
    mij, t: longint;
begin
if (st = poz) and (dr = poz) then
	begin v[nod] := val; exit; end;
mij := (st + dr) shr 1; 
t := nod shl 1;
if (poz <= mij) then
	update (t, st, mij, poz, val)
else
	update (t + 1, mij+1, dr, poz, val);
if (v[t] >= v[t+1]) then v[nod] := v[t] else v[nod] := v[t+1];
end;

begin
assign	(f, 'arbint.in');	assign 	(g, 'arbint.out');
reset	(f);				rewrite	(g);
readln	(f, n, m);
for i := 1 to n do
	begin
	read 	(f, a);
	update	(1, 1, n, i, a);
	end;
readln	(f);
for i := 1 to m do
	begin
	readln	(f, t, a, b);
	if (t = 1) then
		update	(1, 1, n, a, b)
	else
		writeln	(g, query (1, 1, n, a, b));
	end;
close	(f);				close	(g);
end.