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Solved 2020 day 1
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‎src/AdventSolutions/Year2020/Day1/README.md

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### --- Day 1: Report Repair ---
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After saving Christmas five years in a row, you've decided to take a vacation at a nice resort on a tropical island.
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Surely, Christmas will go on without you.
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The tropical island has its own currency and is entirely cash-only. The gold coins used there have a little picture of a
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starfish; the locals just call them stars. None of the currency exchanges seem to have heard of them, but somehow,
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you'll need to find fifty of these coins by the time you arrive so you can pay the deposit on your room.
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To save your vacation, you need to get all fifty stars by December 25th.
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Collect stars by solving puzzles. Two puzzles will be made available on each day in the Advent calendar; the second
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puzzle is unlocked when you complete the first. Each puzzle grants one star. Good luck!
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Before you leave, the Elves in accounting just need you to fix your expense report (your puzzle input); apparently,
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something isn't quite adding up.
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Specifically, they need you to find the two entries that sum to ```2020``` and then multiply those two numbers together.
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For example, suppose your expense report contained the following:
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```
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1721
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979
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366
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299
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675
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1456
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```
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In this list, the two entries that sum to ```2020``` are ```1721``` and ```299```. Multiplying them together
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produces ```1721 * 299 = 514579```, so the correct answer is ```514579```.
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Of course, your expense report is much larger. Find the two entries that sum to ```2020```; what do you get if you
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multiply them together?
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### --- Part Two ---
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The Elves in accounting are thankful for your help; one of them even offers you a starfish coin they had left over from
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a past vacation. They offer you a second one if you can find three numbers in your expense report that meet the same
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criteria.
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Using the above example again, the three entries that sum to ```2020``` are ```979```, ```366```, and ```675```.
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Multiplying them together produces the answer, ```241861950```.
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In your expense report, what is the product of the three entries that sum to ```2020```?

‎src/AdventSolutions/Year2020/Day1/Solution2020Day1.php

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<?php
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namespace App\AdventSolutions\Year2020\Day1;
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use App\AdventSolutions\AbstractSolution;
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class Solution2020Day1 extends AbstractSolution
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{
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public function solvePart1($input): string
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{
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foreach ($input as $value) {
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foreach ($input as $value2) {
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if ($value + $value2 === 2020) {
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return $value * $value2;
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}
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}
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}
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return "No solution found!";
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}
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public function solvePart2($input): string
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{
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foreach ($input as $value) {
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foreach ($input as $value2) {
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foreach ($input as $value3) {
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if ($value + $value2 + $value3 === 2020) {
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return $value * $value2 * $value3;
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}
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}
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}
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}
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return "No solution found!";
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}
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}

‎src/AdventSolutions/Year2020/Day1/input.txt

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1941
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1887
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1851
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1874
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1612
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1960
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1971
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1983
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1406
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1966
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1554
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1892
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1898
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1926
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1081
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1992
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1073
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1603
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177
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1747
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1063
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1969
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1659
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1303
25+
1759
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1853
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1107
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1818
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1672
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1352
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2002
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1838
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1985
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1860
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1141
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1903
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1334
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1489
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1178
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1823
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1499
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1951
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1225
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1503
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1417
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1724
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1165
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1339
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1816
50+
1504
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1588
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1997
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1946
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1324
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1771
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1982
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1272
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1367
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1439
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1252
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1902
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1940
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1333
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1750
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1512
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1538
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1168
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2001
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1797
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1233
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972
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1306
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1835
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1825
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1822
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1880
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1732
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1785
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1727
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1275
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1355
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1793
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1485
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1297
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1932
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1519
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1587
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1382
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1914
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1745
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1087
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1996
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1746
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1962
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1573
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2008
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1868
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1278
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1386
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1238
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1242
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1170
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1476
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1161
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1754
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1807
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1514
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1189
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1916
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1884
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1535
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1217
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1911
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1861
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1493
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1409
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1783
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1222
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1955
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1673
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1502
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607
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2010
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1846
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1819
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1500
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1799
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1475
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1146
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1608
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1806
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1660
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1618
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1904
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978
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1762
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1925
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1185
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1154
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1239
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1843
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1986
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533
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1509
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1913
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287
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1707
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1115
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1699
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1859
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1077
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1915
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1412
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1360
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1646
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1973
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1627
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1755
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1748
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1769
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1886
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1422
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1686
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950
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100
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1372
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1068
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1370
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1428
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1870
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1108
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190
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1891
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1794
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1228
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1128
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1365
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1740
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1888
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1460
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1758
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1906
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1917
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1989
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1251
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1866
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1560
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1921
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1777
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1102
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1850
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1498
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683
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1840
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1800
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1112
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1908
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1442
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1082
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1071

‎src/AdventSolutions/Year2020/Day1/input_test.txt

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1721
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979
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366
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299
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675
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1456

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