day 1

day1/.gitignore

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+/target
+**/*.rs.bk

day1/Cargo.lock

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+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+[[package]]
+name = "day1"
+version = "0.1.0"
+

day1/Cargo.toml

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+[package]
+name = "day1"
+version = "0.1.0"
+authors = ["Stefan Bühler <stbuehler@web.de>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

day1/src/input.txt

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+77680
+106826
+120225
+122031
+100287
+70402
+145496
+73956
+148205
+52065
+149237
+116195
+84309
+105327
+134606
+109489
+104474
+69536
+141469
+72321
+75154
+142565
+57104
+111925
+100109
+75178
+115130
+75586
+148587
+116029
+113969
+66072
+90521
+116324
+137009
+92880
+110895
+131046
+83273
+99576
+70466
+93602
+63435
+103569
+56610
+58392
+95060
+59101
+121838
+93494
+52243
+146982
+142260
+107232
+117600
+59715
+80284
+128223
+123676
+81060
+99425
+50621
+101184
+112136
+131262
+53150
+113522
+117802
+120251
+102322
+111247
+117719
+88873
+133541
+92695
+125445
+149048
+146928
+83909
+109466
+94063
+62338
+124098
+64769
+104722
+106612
+53882
+108847
+92739
+88496
+89773
+57471
+140532
+87308
+137247
+62816
+118893
+101446
+149208
+68267

day1/src/main.rs

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+fn fuel_for_modules1(input: &str) -> i64 {
+	let mut fuel: i64 = 0;
+	for module in input.split_whitespace() {
+		let module: i64 = module.parse().unwrap();
+		fuel += (module / 3) - 2;
+	}
+	fuel
+}
+
+fn fuel_for_mass2(mass: u64) -> u64 {
+	if mass <= 8 { return 0; } /* wish really hard */
+	let fuel = mass / 3 - 2;
+	fuel + fuel_for_mass2(fuel)
+}
+
+fn fuel_for_modules2(input: &str) -> u64 {
+	let mut fuel: u64 = 0;
+	for module in input.split_whitespace() {
+		let module: u64 = module.parse().unwrap();
+		fuel += fuel_for_mass2(module);
+	}
+	fuel
+}
+
+fn main() {
+	let input = include_str!("input.txt");
+	println!("Fuel 1: {}", fuel_for_modules1(input));
+	println!("Fuel 2: {}", fuel_for_modules2(input));
+}