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2019/day01/README.org

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+* --- Day 1: The Tyranny of the Rocket Equation ---
+   :PROPERTIES:
+   :CUSTOM_ID: day-1-the-tyranny-of-the-rocket-equation----
+   :END:
+
+Santa has become stranded at the edge of the Solar System while
+delivering presents to other planets! To accurately calculate his
+position in space, safely align his warp drive, and return to Earth in
+time to save Christmas, he needs you to bring him measurements from
+/fifty stars/.
+
+Collect stars by solving puzzles. Two puzzles will be made available on
+each day in the Advent calendar; the second puzzle is unlocked when you
+complete the first. Each puzzle grants /one star/. Good luck!
+
+The Elves quickly load you into a spacecraft and prepare to launch.
+
+At the first Go / No Go poll, every Elf is Go until the Fuel
+Counter-Upper. They haven't determined the amount of fuel required yet.
+
+Fuel required to launch a given /module/ is based on its /mass/.
+Specifically, to find the fuel required for a module, take its mass,
+divide by three, round down, and subtract 2.
+
+For example:
+
+- For a mass of =12=, divide by 3 and round down to get =4=, then
+  subtract 2 to get =2=.
+- For a mass of =14=, dividing by 3 and rounding down still yields =4=,
+  so the fuel required is also =2=.
+- For a mass of =1969=, the fuel required is =654=.
+- For a mass of =100756=, the fuel required is =33583=.
+
+The Fuel Counter-Upper needs to know the total fuel requirement. To find
+it, individually calculate the fuel needed for the mass of each module
+(your puzzle input), then add together all the fuel values.
+
+/What is the sum of the fuel requirements/ for all of the modules on
+your spacecraft?
+
+To begin, [[file:1/input][get your puzzle input]].
+
+Answer: