pinch-points 0.1.0

A fast, kid-friendly crab-routing game: route streams of crabs into your sandcastle before the tide comes in
Documentation
# The same staircase, walked from the other end and with two crabs on it.
# What sends one down sends the other past the turn.
name: Zigzag
posts: 3
crab: 8,4 L R common
crab: 8,0 L R common
solution: 1,0 D; 6,1 D; 5,2 D
map:
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