AOC2020/aoc2020/lib/aoc20201206.dart

import 'package:aoc2020/aocbase.dart';
import 'package:aoc2020/model/readdata.dart';

class AOC20201206 extends AOCBase {
  int voterTabulation({List<String> rawList, bool isIntersection}) {
    var retval = 0;
    var voterList = <Set<String>>[];
    var agregate = <String>{};
    var voterIndex = 0;

    int processVoters() {
        agregate = voterList[0];
        for (var voter in voterList) {
          agregate = isIntersection ? agregate.intersection(voter) : agregate.union(voter);
        }
        return agregate.length;
    }

    for (var line in rawList) {
      if (line.isEmpty) {
        retval += processVoters();
        voterList = <Set<String>>[];
        voterIndex = 0;
      } else {
        voterList.add({});
        for (var index = 0; index < line.length; index++) {
          voterList[voterIndex].add(line[index]);
        }
        voterIndex++;
      }
    }
    retval += processVoters();
    return retval;
  }

  @override
  Future<void> a({bool test}) async {
    var filename = (test ?? false) ? classStringTest : classString;
    var mylist = await ReadData.readFileString(filename);

    answerA = voterTabulation(rawList: mylist, isIntersection: false);
  }

  @override
  Future<void> b({bool test}) async {
    var filename = (test ?? false) ? classStringTest : classString;
    var mylist = await ReadData.readFileString(filename);

    answerB = voterTabulation(rawList: mylist, isIntersection: true);
  }
}