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.