math - Problem Set - HFOJ

	ID	Problem Show tags Hide tags	AC / Tried	Difficulty
	1644	P1601A Array Elimination bitmasks greedy math number theory *1300	0 / 0	4
	1635	P1601F Two Sorts binary search dfs and similar math meet-in-the-middle *3400	0 / 0	10
	1632	P1603A Di-visible Confusion constructive algorithms math number theory *1300	0 / 0	4
	1631	P1603B Moderate Modular Mode constructive algorithms math number theory *1600	1 / 1	5
	1630	P1603C Extreme Extension dp greedy math number theory *2300	0 / 0	8
	1627	P1603E A Perfect Problem combinatorics dp math *3200	0 / 0	10
	1626	P1603F October 18, 2017 combinatorics dp implementation math *2700	0 / 0	10
	1623	P1605A A.M math number theory *800	0 / 0	3
	1619	P1605E Array Equalizer binary search greedy implementation math number theory sortings two pointers *2400	0 / 0	9
	1615	P1606B Update Files greedy implementation math *1100	0 / 0	3
	1612	P1606E Arena combinatorics dp math *2100	0 / 0	7
	1608	P1607B Odd Grasshopper math *900	0 / 0	3
	1606	P1607D Blue-Red Permutation greedy math sortings *1300	0 / 0	4
	1597	P1608A Find Array constructive algorithms math *800	0 / 0	3
	1590	P1608D Dominoes combinatorics fft graphs math number theory *2400	0 / 0	9
	1583	P1609A Divide and Multiply greedy implementation math number theory *900	0 / 0	3
	1573	P1609G A Stroll Around the Matrix data structures greedy math *3000	0 / 0	10
	1571	P1610A Anti Light's Cell Guessing math *900	0 / 0	3
	1568	P1610D Not Quite Lee combinatorics dp math number theory *2000	0 / 0	7
	1567	P1610E AmShZ and G.O.A.T. binary search brute force greedy implementation math *2300	0 / 0	8
	1562	P1611A Make Even constructive algorithms math *800	0 / 0	3
	1561	P1611B Team Composition: Programmers and Mathematicians binary search constructive algorithms math *800	0 / 0	3
	1552	P1612C Chat Ban binary search math *1300	0 / 0	4
	1551	P1612D X-Magic Pair math number theory *1600	0 / 0	5
	1547	P1613A Long Comparison implementation math *900	0 / 0	3
	1544	P1613D MEX Sequences dp math *1900	0 / 0	6
	1539	P1614C Divan and bitwise operations bitmasks combinatorics constructive algorithms dp math *1500	0 / 0	5
	1535	P1615A Closing The Gap greedy math *800	0 / 0	3
	1534	P1615B And It's Non-Zero bitmasks greedy math *1300	0 / 0	4
	1533	P1615C Menorah brute force graphs greedy math *1600	0 / 0	5
	1531	P1615E Purple Crayon data structures dfs and similar games graphs greedy math sortings trees *2400	0 / 0	9
	1530	P1615F LEGOndary Grandmaster combinatorics dp math *2800	0 / 0	10
	1525	P1616C Representative Edges brute force geometry implementation math *1500	0 / 0	5
	1524	P1616D Keep the Average High dp greedy math *2000	0 / 0	7
	1522	P1616F Tricolor Triangles brute force graphs math matrices *2900	0 / 0	10
	1520	P1616H Keep XOR Low bitmasks combinatorics data structures divide and conquer dp math *3000	0 / 0	10
	1518	P1617B GCD Problem brute force constructive algorithms math number theory *900	0 / 0	3
	1517	P1617C Paprika and Permutation binary search greedy math sortings *1300	0 / 0	4
	1515	P1617D2 Too Many Impostors (hard version) constructive algorithms implementation interactive math *2400	0 / 0	9
	1514	P1617E Christmas Chocolates dfs and similar dp games graphs implementation math number theory shortest paths trees *2700	0 / 0	10
	1513	P1618A Polycarp and Sums of Subsequences math sortings *800	0 / 0	3
	1511	P1618C Paint the Array math *1100	0 / 0	3
	1510	P1618D Array and Operations dp greedy math *1300	0 / 0	4
	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
	1505	P1619B Squares and Cubes implementation math *800	0 / 0	3
	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
	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
	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
	1485	P1621G Weighted Increasing Subsequences data structures dp math *3200	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
	1479	P1622D Shuffle combinatorics math two pointers *2000	0 / 0	7
	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
	1473	P1623D Robot Cleaner Revisit implementation math probabilities *2300	0 / 0	8
	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
	1464	P1625A Ancient Civilization bitmasks greedy math *800	0 / 0	3
	1461	P1625D Binary Spiders bitmasks data structures implementation math sortings trees *2300	0 / 0	8
	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
	1453	P1626F A Random Code Problem combinatorics dp math number theory probabilities *2800	0 / 0	10
	1447	P1627D Not Adding brute force dp math number theory *1900	0 / 0	6
	1441	P1628A Meximum Array binary search constructive algorithms greedy implementation math two pointers *1400	0 / 0	4
	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
	1425	P1629B GCD Arrays greedy math number theory *800	0 / 0	3
	1416	P1630E Expected Components combinatorics math number theory probabilities *2900	0 / 0	10
	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
	1399	P1633C Kill the Monster brute force math *1100	0 / 0	3
	1397	P1633E Spanning Tree Queries binary search data structures dfs and similar dsu graphs greedy math sortings trees *2400	0 / 0	9
	1394	P1634B Fortune Telling bitmasks math *1400	0 / 0	4
	1392	P1634D Finding Zero constructive algorithms interactive math *2000	0 / 0	7
	1390	P1634F Fibonacci Additions brute force data structures hashing implementation math *2700	0 / 0	10
	1386	P1635D Infinite Set bitmasks dp math matrices number theory strings *1800	0 / 0	6
	1382	P1637B MEX and Array brute force dp greedy math *1100	0 / 0	3
	1380	P1637D Yet Another Minimization Problem dp greedy math *1800	0 / 0	6
	1377	P1637G Birthday constructive algorithms greedy math *3000	0 / 0	10
	1376	P1637H Minimize Inversions Number data structures greedy math sortings *3500	0 / 0	10
	1375	P1638A Reverse constructive algorithms greedy math *800	0 / 0	3
	1374	P1638B Odd Swap Sort data structures math sortings *1100	0 / 0	3
	1373	P1638C Inversion Graph data structures dsu graphs math *1300	0 / 0	4
	1355	P1641D Two Arrays bitmasks brute force combinatorics greedy hashing math two pointers *2700	0 / 1	10
	1354	P1641E Special Positions combinatorics divide and conquer fft math *3300	0 / 0	10
	1347	P1644D Cross Coloring data structures implementation math *1700	0 / 0	5
	1346	P1644E Expand the Path brute force combinatorics data structures implementation math *1900	0 / 0	6
	1345	P1644F Basis combinatorics fft math number theory *2900	0 / 0	10
	1344	P1646A Square Counting math *800	0 / 0	3
	1342	P1646C Factorials and Powers of Two bitmasks brute force constructive algorithms dp math *1500	0 / 0	5
	1340	P1646E Power Board brute force dp math number theory *2200	0 / 0	8
	1338	P1647A Madoka and Math Dad implementation math *800	0 / 0	3
	1335	P1647D Madoka and the Best School in Russia constructive algorithms dp math number theory *1900	0 / 0	6
	1332	P1648A Weird Sum combinatorics data structures geometry math matrices sortings *1400	0 / 0	4

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