uses crt;
var vt,n,i,max:longint; a:array[0..100000]of longint;
begin
clrscr;
   write('n=');readln(n);
   max:=low(longint);
   vt:=n;
   for i:=0 to n-1 do
      begin
         write('a[',i,']=');readln(a[i]);
         if(a[i]<0)and(a[i]>max)then begin max:=a[i]; vt:=i; end;
      end;
   if vt<>n then
      begin
         writeln('So hang am lon nhat cua day: ',max);
         writeln('Chi so cua no la: ',vt);
      end else writeln('Khong co so hang am nao trong day!');
readln
end.

test:

uses crt;
var a:array[0..10000000] of longint;
    n,i,min,max,k,j:longint;
begin
clrscr;
write('Nhap do dai day so: ');readln(n);
for i:=0 to n-1 do
  begin
  write('a[',i,']=');readln(a[i]);
  end;
min:=a[0];
for i:=0 to n-1 do if a[i]<min then min:=a[i];
max:=min;
for i:=0 to n-1 do if a[i]<0 then
  begin
  if a[i]>max then
    begin
    max:=a[i];
    k:=i;
    end;
  end;
write('So hang am lon nhat trong day la: a[',k,']=',max);
readln;
end.