diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/main.rs | 196 |
1 files changed, 195 insertions, 1 deletions
diff --git a/src/main.rs b/src/main.rs index 9b7e3f7..a8e6819 100644 --- a/src/main.rs +++ b/src/main.rs @@ -1209,8 +1209,129 @@ fn day13() { println!("13b: {}", arcade.score); } +struct Reaction { + result: String, + amount: isize, + resources: HashMap<String, isize>, +} + +impl Reaction { + fn split_amount_material(input: &str) -> (isize, String) { + let splitted: Vec<&str> = input.split(' ').collect(); + assert_eq!(splitted.len(), 2); + (splitted[0].parse::<isize>().unwrap(), splitted[1].to_string()) + } + + fn parse(input: &str) -> Reaction { + let reaction: Vec<&str> = input.split(" => ").collect(); + let (amount, result) = Reaction::split_amount_material(reaction[1]); + let required = reaction[0].split(", "); + let mut resources = HashMap::new(); + for resource in required { + let (amount, material) = Reaction::split_amount_material(resource); + resources.insert(material, amount); + } + + Reaction { + result, + amount, + resources, + } + } +} + +struct Reactions { + reactions: HashMap<String, Reaction>, +} + +impl Reactions { + const ORE_LIMIT: isize = 1_000_000_000_000; + + fn parse(input: &str) -> Reactions { + let mut reactions = HashMap::new(); + let input = input.trim_end(); + + for line in input.split('\n') { + let reaction = Reaction::parse(line); + reactions.insert(reaction.result.clone(), reaction); + } + Reactions { reactions } + } + + fn count_material_(&self, amount_requested: isize, output: &str, leftovers: &mut HashMap<String, isize>, total_ore_count: &mut isize) -> Result<isize, ()> { + if output == "ORE" { + if *total_ore_count + amount_requested > Reactions::ORE_LIMIT { + return Err(()); + } + *total_ore_count += amount_requested; + return Ok(amount_requested); + } + let mut amount_requested = amount_requested; + + /* use up leftover materials first */ + let leftover = *leftovers.entry(output.to_string()).or_insert(0); + if leftover >= amount_requested { + leftovers.insert(output.to_string(), leftover - amount_requested); + /* no additional reaction needed, can satisfy with leftovers */ + return Ok(0); + } else { + leftovers.insert(output.to_string(), 0); + amount_requested -= leftover; + } + + let reaction = self.reactions.get(output).unwrap(); + let mut factor = amount_requested / reaction.amount; + if amount_requested % reaction.amount > 0 { + factor += 1; + } + let produced = factor * reaction.amount; + leftovers.insert(output.to_string(), produced - amount_requested); + + let mut ore_count = 0; + for resource in reaction.resources.keys() { + let amount = *reaction.resources.get(resource).unwrap(); + ore_count += self.count_material_(amount * factor, &resource, leftovers, total_ore_count)?; + } + + Ok(ore_count) + } + + fn count_material(&self, amount_requested: isize, output: &str, ) -> isize { + let mut ore_count = 0; + self.count_material_(amount_requested, output, &mut HashMap::new(), &mut ore_count).unwrap() + } + + fn possible_fuel(&self) -> isize { + let mut leftovers = HashMap::new(); + let mut ore_count = 0; + + let mut fuel_count = 1; + let ore_per_fuel = self.count_material_(1, "FUEL", &mut leftovers, &mut ore_count).unwrap(); + + fuel_count += Reactions::ORE_LIMIT / ore_per_fuel; + self.count_material_(Reactions::ORE_LIMIT / ore_per_fuel, "FUEL", &mut leftovers, &mut ore_count).unwrap(); + loop { + match self.count_material_(1, "FUEL", &mut leftovers, &mut ore_count) { + Ok(_) => fuel_count += 1, + Err(_) => break, + }; + } + fuel_count + } + +} + +fn day14() { + let input = read_file("input14"); + let reactions = Reactions::parse(&input); + + println!("14a: {}", reactions.count_material(1, "FUEL")); + + println!("14b: {}", reactions.possible_fuel()); +} + fn main() { - day13(); + day14(); } #[cfg(test)] @@ -1415,4 +1536,77 @@ mod tests { assert_eq!(asteroid_map.vaporized(max.0, 200), Point { x: 8, y: 2 }); } + + #[test] + fn test_day14() { + let input = "10 ORE => 10 A\n\ + 1 ORE => 1 B\n\ + 7 A, 1 B => 1 C\n\ + 7 A, 1 C => 1 D\n\ + 7 A, 1 D => 1 E\n\ + 7 A, 1 E => 1 FUEL"; + let reactions = Reactions::parse(input); + assert_eq!(reactions.count_material(1, "FUEL"), 31); + + let input = "9 ORE => 2 A\n\ + 8 ORE => 3 B\n\ + 7 ORE => 5 C\n\ + 3 A, 4 B => 1 AB\n\ + 5 B, 7 C => 1 BC\n\ + 4 C, 1 A => 1 CA\n\ + 2 AB, 3 BC, 4 CA => 1 FUEL"; + let reactions = Reactions::parse(input); + assert_eq!(reactions.count_material(1, "FUEL"), 165); + + + let input = "157 ORE => 5 NZVS\n\ + 165 ORE => 6 DCFZ\n\ + 44 XJWVT, 5 KHKGT, 1 QDVJ, 29 NZVS, 9 GPVTF, 48 HKGWZ => 1 FUEL\n\ + 12 HKGWZ, 1 GPVTF, 8 PSHF => 9 QDVJ\n\ + 179 ORE => 7 PSHF\n\ + 177 ORE => 5 HKGWZ\n\ + 7 DCFZ, 7 PSHF => 2 XJWVT\n\ + 165 ORE => 2 GPVTF\n\ + 3 DCFZ, 7 NZVS, 5 HKGWZ, 10 PSHF => 8 KHKGT"; + let reactions = Reactions::parse(input); + assert_eq!(reactions.count_material(1, "FUEL"), 13312); + //assert_eq!(reactions.possible_fuel(), 82892753); + + let input = "2 VPVL, 7 FWMGM, 2 CXFTF, 11 MNCFX => 1 STKFG\n\ + 17 NVRVD, 3 JNWZP => 8 VPVL\n\ + 53 STKFG, 6 MNCFX, 46 VJHF, 81 HVMC, 68 CXFTF, 25 GNMV => 1 FUEL\n\ + 22 VJHF, 37 MNCFX => 5 FWMGM\n\ + 139 ORE => 4 NVRVD\n\ + 144 ORE => 7 JNWZP\n\ + 5 MNCFX, 7 RFSQX, 2 FWMGM, 2 VPVL, 19 CXFTF => 3 HVMC\n\ + 5 VJHF, 7 MNCFX, 9 VPVL, 37 CXFTF => 6 GNMV\n\ + 145 ORE => 6 MNCFX\n\ + 1 NVRVD => 8 CXFTF\n\ + 1 VJHF, 6 MNCFX => 4 RFSQX\n\ + 176 ORE => 6 VJHF"; + let reactions = Reactions::parse(input); + assert_eq!(reactions.count_material(1, "FUEL"), 180697); + //assert_eq!(reactions.possible_fuel(), 5586022); + + let input = "171 ORE => 8 CNZTR\n\ + 7 ZLQW, 3 BMBT, 9 XCVML, 26 XMNCP, 1 WPTQ, 2 MZWV, 1 RJRHP => 4 PLWSL\n\ + 114 ORE => 4 BHXH\n\ + 14 VRPVC => 6 BMBT\n\ + 6 BHXH, 18 KTJDG, 12 WPTQ, 7 PLWSL, 31 FHTLT, 37 ZDVW => 1 FUEL\n\ + 6 WPTQ, 2 BMBT, 8 ZLQW, 18 KTJDG, 1 XMNCP, 6 MZWV, 1 RJRHP => 6 FHTLT\n\ + 15 XDBXC, 2 LTCX, 1 VRPVC => 6 ZLQW\n\ + 13 WPTQ, 10 LTCX, 3 RJRHP, 14 XMNCP, 2 MZWV, 1 ZLQW => 1 ZDVW\n\ + 5 BMBT => 4 WPTQ\n\ + 189 ORE => 9 KTJDG\n\ + 1 MZWV, 17 XDBXC, 3 XCVML => 2 XMNCP\n\ + 12 VRPVC, 27 CNZTR => 2 XDBXC\n\ + 15 KTJDG, 12 BHXH => 5 XCVML\n\ + 3 BHXH, 2 VRPVC => 7 MZWV\n\ + 121 ORE => 7 VRPVC\n\ + 7 XCVML => 6 RJRHP\n\ + 5 BHXH, 4 VRPVC => 5 LTCX"; + let reactions = Reactions::parse(input); + assert_eq!(reactions.count_material(1, "FUEL"), 2210736); + //assert_eq!(reactions.possible_fuel(), 460664); + } } |