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Hot problems
CCC '25 S5 - To-Do List
DMOPC '18 Contest 4 P2 - Dr. Henri and Responsibility
Maximum Sum
UTS Open '21 P4 - Lucky Graph
COCI '23 Contest 5 #1 Zlagalica
Longest Increasing Subsequence
CCC '25 S4 - Floor is Lava
Problem
Category
Points
AC %
Users
CCC '00 J1 - Calendar
CCC
5p
11.2%
1527
CCC '00 S1 - Slot Machines
CCC
5p
27.0%
5071
CCC '01 S1 - Keeping Score
CCC
5p
32.9%
1666
CCC '01 S2 - Spirals
CCC
5p
40.3%
1004
CCC '02 S1 - The Students' Council Breakfast
CCC
5p
39.7%
1638
CCC '02 S2 - Fraction Action
CCC
5p
19.4%
2046
CCC '03 S1 - Snakes and Ladders
CCC
5p
20.7%
3275
CCC '03 S2 - Poetry
CCC
5p
17.6%
1589
CCC '04 J4 - Simple Encryption
CCC
5p
50.8%
1871
CCC '04 S1 - Fix
CCC
5p
31.6%
1306
CCC '04 S2 - TopYodeller
CCC
5p
21.0%
802
CCC '05 J3 - Returning Home
CCC
5p
36.6%
2561
CCC '05 S1 - Snow Calls
CCC
5p
43.4%
2441
CCC '05 S2 - Mouse Move
CCC
5p
37.4%
1806
CCC '06 S1 - Maternity
CCC
5p
37.1%
1218
CCC '06 S2 - Attack of the CipherTexts
CCC
5p
5.8%
333
CCC '07 J4 - Anagram Checker
CCC
5p
37.5%
2364
CCC '07 S2 - Boxes
CCC
5p
27.1%
1309
CCC '08 S1 - It's Cold Here!
CCC
5p
37.7%
2329
CCC '08 S2 - Pennies in the Ring
CCC
5p
31.0%
1282
CCC '09 J2 - Old Fishin' Hole
CCC
5p
38.4%
1820
CCC '09 J3 - Good Times
CCC
5p
20.3%
1555
CCC '09 S1 - Cool Numbers
CCC
5p
23.1%
2157
CCC '10 J2 - Up and Down
CCC
5p
22.0%
2264
CCC '10 J3 - Punchy
CCC
5p
32.8%
1551
CCC '10 J4 - Global Warming
CCC
5p
22.7%
1147
CCC '10 S1 - Computer Purchase
CCC
5p
14.4%
1441
CCC '10 S2 - Huffman Encoding
CCC
5p
53.5%
1739
CCC '11 J2 - Who Has Seen The Wind
CCC
5p
25.9%
2113
CCC '11 J3 - Sumac Sequences
CCC
5p
42.8%
3215
CCC '11 S1 - English or French?
CCC
5p
35.3%
6443
CCC '12 S2 - Aromatic Numbers
CCC
5p
53.7%
1873
CCC '13 J4 - Time on task
CCC
5p
44.7%
3334
CCC '13 S1 - From 1987 to 2013
CCC
5p
46.5%
4389
CCC '13 S2 - Bridge Transport
CCC
5p
26.7%
2215
CCC '14 S1 - Party Invitation
CCC
5p
47.4%
3821
CCC '14 S2 - Assigning Partners
CCC
5p
33.5%
3080
CCC '15 J3 - Rövarspråket
CCC
5p
38.6%
2552
CCC '15 J4 - Wait Time
CCC
5p
38.8%
1476
CCC '15 S2 - Jerseys
CCC
5p
27.2%
2138
CCC '16 J3 - Hidden Palindrome
CCC
5p
46.2%
2910
CCC '16 J4 - Arrival Time
CCC
5p
28.6%
1867
CCC '16 S2 - Tandem Bicycle
CCC
5p
53.5%
3828
CCC '17 J4 - Favourite Times
CCC
5p
23.6%
1760
CCC '17 S2 - High Tide, Low Tide
CCC
5p
27.8%
3107
CCC '18 S2 - Sunflowers
CCC
5p
39.8%
3122
CCC '19 J3 - Cold Compress
CCC
5p
46.1%
3756
CCC '19 S2 - Pretty Average Primes
CCC
5p
26.2%
2613
CCC '20 J4 - Cyclic Shifts
CCC
5p
46.0%
2655
CCC '20 S1 - Surmising a Sprinter's Speed
CCC
5p
43.2%
2326
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