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kiss-vscode/projects/_standalone/aoc/src/year2021/day7.kiss

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(function crabPositions [file]
(map (.split (first (Util.readLines file)) ",") Std.parseInt))
(function :Int summation [n]
(/ (* n (+ 1 n)) 2))
(function :Int fuelToAlignAt [x :Array<Int> positions &opt :Bool part2]
(apply + (for crabX positions
(let [distance (Math.abs (- x crabX))]
(if part2
(summation distance)
distance)))))
(function :Int bestPosToAlignAt [:Array<Int> positions &opt :Bool part2]
(let [&mut minX (apply min positions)
&mut maxX (apply max positions)]
(loop
(let [middleX (Math.floor (/ (+ minX maxX) 2))
middleFuel (fuelToAlignAt middleX positions ?part2)
leftBy1Fuel (fuelToAlignAt (- middleX 1) positions ?part2)
rightBy1Fuel (fuelToAlignAt (+ middleX 1) positions ?part2)]
~[minX middleX maxX]
(cond
((= minX middleX maxX)
(throw ""))
((< middleFuel (min leftBy1Fuel rightBy1Fuel))
(return middleX))
((< leftBy1Fuel middleFuel)
(set maxX middleX))
((< rightBy1Fuel middleFuel)
(set minX middleX)))))
(throw "")))