Advent of Code 2023 - Day 5 - Salesforce Apex

--- Day 5: If You Give A Seed A Fertilizer ---

https://adventofcode.com/2023/day/5

Advent Calendar Progress

Day 05 - Solution

	public with sharing class day05 {
	public static Integer part1(List<String> puzzleInputLines, String fullInput) {
	String seedRow = puzzleInputLines.remove(0);
	String[] seedValues = seedRow.split(': ')[1].split(' ');
	List<Seed> seeds = new List<Seed>();
	for(Integer i = 0; i < seedValues.size(); i += 2) {
	seeds.add(new Seed(Double.valueOf(seedValues[i]), Double.valueOf(seedValues[i + 1])));
	}
	List<String> contentRows = fullInput.split('\n\n');
	contentRows.remove(0);
	List<Map<String, Object>> parsed = new List<Map<String, Object>>();
	for(String content : contentRows) {
	Map<String, Object> parsedMap = parseMap(content);
	parsed.add(parsedMap);
	}
	System.debug(parsed);
	for(Map<String, Object> p : parsed) {
	List<Range> mapList = (List<Range>)p.get('map');
	p.put('map', createNegativeRanges(mapList));
	}
	Map<String, Object> parsedMap = new Map<String, Object>();
	for(Object x : parsed) {
	Map<String, Object> parsedObject = (Map<String, Object>)x;
	String key = (String)parsedObject.get('from');
	parsedMap.put(key, parsedObject);
	}
	System.debug(parsedMap);
	Double lowest = 99999999999999.0; // Use a large number to represent positive infinity
	for(Seed seed : seeds) {
	System.debug('start ' + seed);
	Double remaining = seed.length;
	Double start = seed.start;
	while(remaining > 0) {
	List<Double> walkResult = walk(start, remaining, 'seed', parsedMap);
	Double startLocation = walkResult[0];
	Double consumed = walkResult[1];
	remaining -= consumed;
	start += consumed;
	if(consumed > 1) {
	System.debug('consumed ' + consumed);
	}
	if(startLocation < lowest) {
	lowest = startLocation;
	}
	}
	System.debug('finished ' + seed);
	}
	System.debug(lowest);
	return 0;
	}
	public static Double highestValuePossible = 0;
	private static List<Range> createRange(List<String> rangeStrings) {
	List<Range> rangeList = new List<Range>();
	for (String rangeString : rangeStrings) {
	Range range = createRange(rangeString);
	rangeList.add(range);
	}
	return rangeList;
	}
	public static Range createRange(String line) {
	String[] items = line.split(' ');
	Range range = new Range(
	Integer.valueOf(items[0]), // dest
	Integer.valueOf(items[1]), // varSrc
	Integer.valueOf(items[2]) // varRange
	);
	highestValuePossible = Math.max(highestValuePossible,
	Math.max(
	range.src + range.range,
	range.dest + range.range
	)
	);
	return range;
	}
	public static List<Range> createNegativeRanges(List<Range> ranges) {
	ranges.sort();
	Integer start = 0;
	for(Integer i = 0; i < ranges.size(); i++) {
	Range range = ranges[i];
	if(range.src > start) {
	ranges.add(i, new Range(
	start,
	start,
	range.src - start
	));
	i++;
	}
	start = range.src + range.range;
	}
	return ranges;
	}
	public static Map<String, Object> parseMap(String data) {
	List<String> contents = data.split('\n');
	for (Integer i = contents.size() - 1; i >= 0; i--) {
	if (contents[i].trim() == '') {
	contents.remove(i);
	}
	}
	List<String> rangeData = contents.remove(0).split(' ')[0].split('-');
	String fromVal = rangeData[0];
	String to = rangeData[2];
	Map<String, Object> result = new Map<String, Object>{
	'from' => fromVal,
	'to' => to,
	'map' => createRange(contents)
	};
	return result;
	}
	public static List<Double> walk(Double value, Double range, String name, Map<String, Object> objMap) {
	if (!objMap.containsKey(name)) {
	return new List<Double>{value, range};
	}
	Map<String, Object> item = (Map<String, Object>)objMap.get(name);
	List<Range> rangeList = (List<Range>)item.get('map');
	for(Range rangeItem : rangeList) {
	if (rangeItem.src <= value && value < rangeItem.src + rangeItem.range) {
	Double diff = value - rangeItem.src;
	Double newValue = rangeItem.dest + diff;
	return walk(newValue, Math.min(range, rangeItem.range - diff), (String)item.get('to'), objMap);
	}
	}
	return walk(value, 1, (String)item.get('to'), objMap);
	}
	public class Range implements Comparable {
	public Integer dest {get;set;}
	public Integer src {get;set;}
	public Integer range {get;set;}
	public Range(Integer varDest, Integer varSrc, Integer varRange) {
	dest = varDest;
	src = varSrc;
	range = varRange;
	}
	public Integer compareTo(Object obj) {
	Range otherRange = (Range)obj;
	return (Integer)this.src - (Integer)otherRange.src;
	}
	}
	public class Seed {
	public Double start {get;set;}
	public Double length {get;set;}
	public Seed(Double varStart, Double varLength) {
	start = varStart;
	length = varLength;
	}
	}
	}
	/* example input
	seeds: 79 14 55 13
	seed-to-soil map:
	50 98 2
	52 50 48
	soil-to-fertilizer map:
	0 15 37
	37 52 2
	39 0 15
	fertilizer-to-water map:
	49 53 8
	0 11 42
	42 0 7
	57 7 4
	water-to-light map:
	88 18 7
	18 25 70
	light-to-temperature map:
	45 77 23
	81 45 19
	68 64 13
	temperature-to-humidity map:
	0 69 1
	1 0 69
	humidity-to-location map:
	60 56 37
	56 93 4
	*/

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