program Project1;

{$APPTYPE CONSOLE}

uses
  SysUtils;

var
  n, i, j: integer;
  max1, max2, min1, min2, data: int64;

function min(a, b: int64): int64;
begin
  if (abs(a) >= 1600080001) then
    a := 1600080001;
  if (abs(b) >= 1600080001) then
    b := 1600080001;
  if (a > b) then
    min := b
  else
    min := a;
end;

begin
  readln(n);
  //randomize;
  //n := 100000;
  min1 := 40001;
  min2 := min1;
  max1 := -40001;
  max2 := max1;

  for i := 1 to n do
  begin
    read(data);
    //data := random(40000) - random(40000);
    if (data > max1) then
    begin
      max2 := max1;
      max1 := data;
    end
    else
      if (data > max2) then
        max2 := data;
    if (data < min1) then
    begin
      min2 := min1;
      min1 := data;
    end
    else
      if (data < min2) then
        min2 := data;
  end;
  writeln(min(min1 * max1, min(min1 * min2, max1 * max2)));
  readln;
  readln;
end.