Problem Set - HFOJ

	ID	Problem Show tags Hide tags	AC / Tried	Difficulty
	1509	P1618E Singers' Tour constructive algorithms math *1700	0 / 0	5
	1508	P1618F Reverse bitmasks constructive algorithms dfs and similar implementation math strings *2000	0 / 0	7
	1507	P1618G Trader Problem data structures dsu greedy sortings *2200	0 / 0	8
	1506	P1619A Square String? implementation strings *800	0 / 0	3
	1505	P1619B Squares and Cubes implementation math *800	0 / 0	3
	1504	P1619C Wrong Addition implementation *1200	0 / 0	4
	1503	P1619D New Year's Problem binary search greedy sortings *1800	0 / 0	6
	1502	P1619E MEX and Increments constructive algorithms data structures dp greedy implementation math sortings *1700	0 / 0	5
	1501	P1619F Let's Play the Hat? brute force constructive algorithms greedy math *2000	0 / 0	7
	1500	P1619G Unusual Minesweeper binary search dfs and similar dsu greedy sortings *2000	0 / 0	7
	1499	P1619H Permutation and Queries brute force data structures divide and conquer two pointers *2400	0 / 0	9
	1498	P1620A Equal or Not Equal constructive algorithms dsu implementation *800	0 / 0	3
	1497	P1620B Triangles on a Rectangle geometry greedy math *1000	0 / 0	3
	1496	P1620C BA-String brute force dp greedy implementation math *1800	0 / 0	6
	1495	P1620D Exact Change brute force constructive algorithms greedy *2000	0 / 0	7
	1494	P1620E Replace the Numbers constructive algorithms data structures dsu implementation *1900	0 / 0	6
	1493	P1620F Bipartite Array dp greedy *2800	0 / 0	10
	1492	P1620G Subsequences Galore bitmasks combinatorics dp *2400	0 / 0	9
	1491	P1621A Stable Arrangement of Rooks constructive algorithms *800	0 / 0	3
	1490	P1621B Integers Shop data structures greedy implementation *1500	0 / 0	5
	1489	P1621C Hidden Permutations dfs and similar interactive math *1700	0 / 0	5
	1488	P1621D The Winter Hike constructive algorithms greedy math *2100	0 / 0	7
	1487	P1621E New School binary search data structures dp greedy implementation sortings *2300	0 / 0	8
	1486	P1621F Strange Instructions data structures greedy implementation *2700	0 / 0	10
	1485	P1621G Weighted Increasing Subsequences data structures dp math *3200	0 / 0	10
	1484	P1621H Trains and Airplanes dfs and similar graphs shortest paths trees *3500	0 / 0	10
	1483	P1621I Two Sequences data structures hashing string suffix structures *3500	0 / 0	10
	1482	P1622A Construct a Rectangle geometry math *800	0 / 0	3
	1481	P1622B Berland Music data structures greedy math sortings *1000	0 / 0	3
	1480	P1622C Set or Decrease binary search brute force greedy sortings *1600	0 / 0	5
	1479	P1622D Shuffle combinatorics math two pointers *2000	0 / 0	7
	1478	P1622E Math Test bitmasks brute force greedy *2200	0 / 0	8
	1477	P1622F Quadratic Set constructive algorithms hashing math number theory *2900	0 / 0	10
	1476	P1623A Robot Cleaner brute force implementation math *800	1 / 3	3
	1475	P1623B Game on Ranges brute force dfs and similar implementation sortings *1100	0 / 0	3
	1474	P1623C Balanced Stone Heaps binary search greedy *1600	0 / 0	5
	1473	P1623D Robot Cleaner Revisit implementation math probabilities *2300	0 / 0	8
	1472	P1623E Middle Duplication data structures dfs and similar greedy strings trees *2500	0 / 0	9
	1471	P1624A Plus One on the Subset math *800	0 / 0	3
	1470	P1624B Make AP implementation math *900	0 / 0	3
	1469	P1624C Division by Two and Permutation constructive algorithms flows graph matchings greedy math *1100	0 / 0	3
	1468	P1624D Palindromes Coloring binary search greedy sortings strings *1400	0 / 0	4
	1467	P1624E Masha-forgetful brute force constructive algorithms dp hashing implementation strings *2000	0 / 0	7
	1466	P1624F Interacdive Problem binary search constructive algorithms interactive *2000	0 / 0	7
	1465	P1624G MinOr Tree bitmasks dfs and similar dsu graphs greedy *1900	0 / 0	6
	1464	P1625A Ancient Civilization bitmasks greedy math *800	0 / 0	3
	1463	P1625B Elementary Particles brute force greedy sortings *1100	0 / 0	3
	1462	P1625C Road Optimization dp *1700	0 / 0	5
	1461	P1625D Binary Spiders bitmasks data structures implementation math sortings trees *2300	0 / 0	8
	1460	P1625E1 Cats on the Upgrade (easy version) brute force data structures dfs and similar divide and conquer dp graphs trees *2500	0 / 0	9
	1459	P1625E2 Cats on the Upgrade (hard version) binary search data structures dfs and similar graphs trees *2800	0 / 0	10
	1458	P1626A Equidistant Letters constructive algorithms sortings *800	0 / 0	3
	1457	P1626B Minor Reduction greedy strings *1100	0 / 0	3
	1456	P1626C Monsters And Spells binary search data structures dp greedy implementation math two pointers *1700	0 / 0	5
	1455	P1626D Martial Arts Tournament binary search brute force greedy math *2100	0 / 0	7
	1454	P1626E Black and White Tree dfs and similar greedy trees *2400	0 / 0	9
	1453	P1626F A Random Code Problem combinatorics dp math number theory probabilities *2800	0 / 0	10
	1452	P1627A Not Shading constructive algorithms implementation *800	0 / 0	3
	1451	P1627B Not Sitting games greedy sortings *1300	0 / 0	4
	1449	P1627C Not Assigning constructive algorithms dfs and similar number theory trees *1400	0 / 0	4
	1447	P1627D Not Adding brute force dp math number theory *1900	0 / 0	6
	1446	P1627E Not Escaping data structures dp implementation shortest paths two pointers *2200	0 / 0	8
	1443	P1627F Not Splitting geometry graphs greedy implementation shortest paths *2700	0 / 0	10
	1441	P1628A Meximum Array binary search constructive algorithms greedy implementation math two pointers *1400	0 / 0	4
	1439	P1628B Peculiar Movie Preferences greedy strings *1700	0 / 0	5
	1437	P1628C Grid Xor constructive algorithms greedy implementation interactive math *2300	0 / 0	8
	1435	P1628D1 Game on Sum (Easy Version) combinatorics dp games math *2100	0 / 0	7
	1434	P1628D2 Game on Sum (Hard Version) combinatorics dp games math *2400	0 / 0	9
	1431	P1628E Groceries in Meteor Town binary search data structures dsu trees *3100	0 / 0	10
	1429	P1628F Spaceship Crisis Management binary search data structures geometry sortings *3500	0 / 0	10
	1427	P1629A Download More RAM brute force greedy sortings *800	0 / 0	3
	1425	P1629B GCD Arrays greedy math number theory *800	0 / 0	3
	1423	P1630A And Matching bitmasks constructive algorithms *1500	0 / 0	5
	1421	P1630B Range and Partition binary search constructive algorithms data structures greedy two pointers *1800	0 / 0	6
	1419	P1630C Paint the Middle dp greedy sortings two pointers *2200	0 / 0	8
	1417	P1630D Flipping Range constructive algorithms dp greedy number theory *2400	0 / 0	9
	1416	P1630E Expected Components combinatorics math number theory probabilities *2900	0 / 0	10
	1414	P1630F Making It Bipartite flows graph matchings graphs number theory *3400	0 / 0	10
	1411	P1631A Min Max Swap greedy *800	0 / 0	3
	1410	P1631B Fun with Even Subarrays dp greedy *1100	0 / 0	3
	1408	P1632A ABC implementation *800	0 / 0	3
	1407	P1632B Roof Construction bitmasks constructive algorithms *1000	0 / 0	3
	1406	P1632C Strange Test binary search bitmasks brute force dp math *1600	0 / 0	5
	1404	P1632D New Year Concert binary search data structures greedy math number theory two pointers *2000	0 / 0	7
	1403	P1632E1 Distance Tree (easy version) binary search data structures dfs and similar graphs shortest paths trees *2400	0 / 0	9
	1402	P1632E2 Distance Tree (hard version) binary search dfs and similar shortest paths trees *2700	0 / 0	10
	1401	P1633A Div brute force *800	0 / 0	3
	1400	P1633B Minority greedy *800	2 / 2	3
	1399	P1633C Kill the Monster brute force math *1100	0 / 0	3
	1398	P1633D Make Them Equal dp greedy *1600	0 / 0	5
	1397	P1633E Spanning Tree Queries binary search data structures dfs and similar dsu graphs greedy math sortings trees *2400	0 / 0	9
	1396	P1633F Perfect Matching data structures divide and conquer interactive trees *2800	0 / 0	10
	1395	P1634A Reverse and Concatenate greedy strings *800	0 / 0	3
	1394	P1634B Fortune Telling bitmasks math *1400	0 / 0	4
	1393	P1634C OKEA constructive algorithms *1000	0 / 0	3
	1392	P1634D Finding Zero constructive algorithms interactive math *2000	0 / 0	7
	1391	P1634E Fair Share constructive algorithms data structures dfs and similar graph matchings graphs *2400	0 / 0	9
	1390	P1634F Fibonacci Additions brute force data structures hashing implementation math *2700	0 / 0	10
	1389	P1635A Min Or Sum bitmasks greedy *800	0 / 0	3
	1388	P1635B Avoid Local Maximums greedy *800	0 / 0	3

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