Alternate sums
Walker czp001 liuguangxi a_forsteri Min_25 C3PO Philippe_57721 mathpseudo sinan hervas lesnik7 nielkh
Public  3w:6d  4xp  Math  70.6% 
How many different values can the expression $ 1 \pm 2 \pm 3 \pm \dots \pm n$ take?
Give your answer for $n = 1000000$
[My timing: instant]
Give your answer for $n = 1000000$
[My timing: instant]
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