Mathe Problem 1+2-3 ... +99-100

[Dax]

So könnts gehen:

Delphi-Quellcode:

var
  Num, i: Integer;
  b: Boolean;

Num := 1;
b := True;
for i := 2 to 100 do
begin
  if b then
    Num := Num + i
  else
    Num := Num - i;
  b := not b;
end;