program pascal;
var arb,v:array[1..200000] of longint;
    n,m,i,j,x,a,b,poz,max:longint;

function mx(a,b:longint):longint;
begin
    if a>b then mx:=a
           else mx:=b;
   end;

procedure update(nod,l,r:longint);
var m:longint;
begin
//fac un fel de cautare binara ca sa gasesc unde e pozitia X
m:=(l+r) div 2;
if (l=poz)and(r=poz) then
   begin
   arb[nod]:=x;
   exit;
   end;
if poz<=m then update(nod*2,l,m)
          else update(nod*2+1,m+1,r);
   //vad care din cei 2 fii e mai mare
arb[nod]:=mx(arb[2*nod],arb[2*nod+1]);
end;

procedure query(nod,l,r:longint);
var m:longint;
begin
//verific daca am tot intervalu curent inclus in ce-mi trebe
if (l>=a)and(r<=b) then
     begin
     if arb[nod]>max then max:=arb[nod];
     exit;
     end;
//daca am de ce merge in stanga ma duc
m:=(l+r) div 2;
if a<=m then query(2*nod,l,m);
if b>m then  query(2*nod+1,m+1,r);
end;

begin
assign(input,'arbint.in');reset(input);
assign(output,'arbint.out');rewrite(output);
readln(n,m);
for i:=1 to n do
    begin
    read(x);
    poz:=i;
    update(1,1,n);
    end;
for i:=1 to m do
    begin
    readln(x,a,b);
    if x=0 then
       begin
       max:=-1;
       query(1,1,n);
       writeln(max);
       end
   else
       begin
       x:=b;
       poz:=a;
       update(1,1,n);
       end;
    end;
close(input); close(output);
end.