uses crt;
var i,max,min,ma,n:longint; a,b:array[1..1000000]of longint;
begin
clrscr;
write('Nhap so luong phan tu: ');readln(n);
for i:=1 to n do
begin
write('Nhap phan tu thu ',i,': ');readln(a[i]);
if i=1 then begin max:=a[i]; min:=a[i]; end;
if a[i]>max then max:=a[i];
if a[i]<min then min:=a[i];
if a[i]<0 then b[a[i]]:=1;
end;
writeln('So lon nhat: ',max);
writeln('So nho nhat: ',min);
write('Mang phu B: ');
for i:=1 to max do write(b[i],' '); writeln;
for i:=1 to n do
if (a[i]<=max)and(abs(max-a[i])*abs(max+a[i])>ma) then ma:=abs(max-a[i])*abs(max+a[i]);
for i:=1 to n do
if (a[i]<=max)and(abs(max-a[i])*abs(max+a[i])=ma) then
writeln('x=',max,'; y=',a[i]);
readln
end.
