const   fin = 'arbint.in'; fout = 'arbint.out';

type    arborele = array[1..100000] of longword;
        buffer = array[1..1 shl 17] of char;

var     arb : arborele;
        bufin, bufout : buffer;
        n ,x ,y ,r : longword;

function max( a ,b : longword ) : longword;
begin
        if (a > b) then max := a else max := b;
end;

procedure construieste( nod ,st ,dr : longword );
var     mij : longword;
begin
        if (st = dr) then read( arb[nod] ) else
        begin
                mij := (st + dr) div 2;
                construieste( 2 * nod ,st ,mij );
                construieste( 2 * nod + 1, mij + 1, dr);
                arb[nod] := max( arb[2 * nod], arb[2 * nod + 1] );
        end;
end;

procedure reface( nod ,st ,dr : longword );
var     mij : longword;
begin
        if (st = dr) then arb[nod] := y else
        begin
                mij := (st + dr) div 2;
                if (x <= mij) then reface( 2 * nod ,st ,mij ) else
                                   reface( 2 * nod + 1, mij + 1, dr );
                arb[nod] := max( arb[2 * nod] ,arb[2 * nod + 1] );
        end;
end;

procedure interogheaza( nod ,st ,dr : longword );
var     mij : longword;
begin
        if (x <= st) and (dr <= y) then
        begin
                if (r < arb[nod]) then r := arb[nod];
                exit();
        end;
        mij := (st + dr) div 2;
        if (x <= mij) then interogheaza( 2 * nod, st, mij );
        if (mij < y) then interogheaza( 2 * nod + 1, mij + 1, dr );
end;

procedure main();
var
        m ,i : longword;
        op : byte;
begin
        assign( input , fin ); reset( input );
        assign( output , fout ); rewrite( output );
        settextbuf( input , bufin );
        settextbuf( output , bufout );
        readln( n ,m );

        construieste( 1, 1, n );
        for i := 1 to m do
        begin
                readln( op, x, y );
                if (op = 1) then reface( 1, 1, n ) else
                begin
                        r := 0;
                        interogheaza( 1, 1, n );
                        write( r, #10 );
                end;
        end;
end;

begin
        main();
end.