-- Arrow Sudoku by Eric Fox
-- https://app.crackingthecryptic.com/sudoku/DGT6HQ46FN

# 3
-- single-digit arrows
b7 = a7 + a6
b7 = b6 + b5 + b4

c6 = d6 + e6 + f6
f7 = g6 + h6
g1 = f2 + e2

h2 = g3 + g4 + g5
h5 = h4 + h3

-- double-digit arrows
(10 * c1) + c2 = d1 + d2 + d3 + e4
(10 * c4) + c5 = d5 + d4 + e3 + f3
(10 * c7) + c8 = c9 + b9
-- note: i9 + i8 + i7 + i6 + i5 + i4 + i3 + i2 + i1 is always equal to 45; otherwise not finished after 12m
(10 * f8) + f9 = g8 + h9 + 45 + h1
