data Vector
= V
{ x
:: Int, y
:: Int } deriving Show
instance Num Vector
where (V x0 y0) + (V x1 y1) = V (x0+x1) (y0+y1)
print $ (V
1 3) + (V
6 9)
ZGF0YSBWZWN0b3IgPSBWIHsgeCA6OiBJbnQsIHkgOjogSW50IH0gZGVyaXZpbmcgU2hvdwoKaW5zdGFuY2UgTnVtIFZlY3RvciB3aGVyZQogICAgKFYgeDAgeTApICsgKFYgeDEgeTEpID0gViAoeDAreDEpICh5MCt5MSkKCm1haW4gPSBkbyBwcmludCAkIDEgKyAyCiAgICAgICAgICBwcmludCAkIChWIDEgMykgKyAoViA2IDkp