Day 1

.gitignore

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+.session
+*.rkt~
+input.*.txt
+.envrc

1.rkt

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+#lang racket
+
+(define input (file->list "input.1.txt"))
+
+(define (mass->fuel mass)
+  (- (floor (/ mass 3)) 2))
+
+; part 1
+(displayln (foldr + 0 (map mass->fuel input)))
+
+(define (mass->fuel* mass)
+  (let ([fuel (mass->fuel mass)])
+    (cond [(<= fuel 0) 0]
+          [else (+ fuel (mass->fuel* fuel))])))
+
+; part 2
+(displayln (foldr + 0 (map mass->fuel* input)))

get-input

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+#!/bin/bash
+
+session=$(cat .session)
+curl -SsH "Cookie: session=$session" https://adventofcode.com/2019/day/$1/input > input.$1.txt