xpqz

⎕FR ⎕PP ⎕IO←1287 34 0
'iotag' 'cmat' 'foldl'⎕CY'dfns'

⍝ https://adventofcode.com/2021/day/1
1⊥2<⌿d←⍎¨⊃⎕NGET'../d/1'1⋄(¯3↓d)+.<3↓d   ⍝ Note: a+b+c<b+c+d is equivalent to a<d

⍝ https://adventofcode.com/2021/day/2
d←↑' '(≠⊆⊢)¨⊃⎕NGET'../d/2'1
(fw dn up)←+/m←('forward' 'down' 'up'∘.≡⊣/d)×⍤1⍎¨⊢/d
fw×dn-up