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Hot problems
CCC '21 J3 - Secret Instructions
CCC '24 S2 - Heavy-Light Composition
DMOPC '20 Contest 4 P1 - Missing Numbers
COCI '06 Regional #3 Firefly
CCC '17 J4 - Favourite Times
ACSL '09 Practice P4 - Rank
UHCC1 P2 - String
Problem
Category
Points
AC %
Users ▾
CCO '22 P1 - Alternating Heights
CCO
12p
27.6%
138
CCO '19 P5 - Marshmallow Molecules
CCO
15p
26.5%
128
CCO '18 P5 - Boring Lectures
CCO
20p
19.2%
126
CCO '04 P1 - Scribble
CCO
5
42.8%
126
CCO '04 P5 - Jengaism
CCO
7
31.8%
116
CCO '18 P2 - Wrong Answer
CCO
12p
15.4%
115
CCO '11 P1 - Putnam
CCO
7
27.6%
108
CCO '08 P1 - Moving Day
CCO
7p
30.5%
106
CCO '22 P2 - Rainy Markets
CCO
17p
18.6%
104
CCO '12 P3 - Mhocskian Languages
CCO
20p
49.6%
103
CCO '15 P5 - Timpanist
CCO
20p
36.5%
102
CCO '02 P5 - Connect The Campus
CCO
12
31.0%
101
CCO '17 P3 - Vera and Modern Art
CCO
30p
14.1%
93
CCO '20 P4 - Travelling Salesperson
CCO
25p
19.6%
92
CCO '05 P4 - Primed Sequences
CCO
12p
12.6%
92
CCO '13 P4 - A Romantic Movie Outing
CCO
20p
23.5%
91
CCO '16 P2 - Splitting Hares
CCO
15p
14.2%
89
CCO '96 P2 - SafeBreaker
CCO
10
36.2%
89
CCO '14 P5 - Early Exam Evacuation
CCO
20p
23.3%
87
CCO '19 P1 - Human Error
CCO
10p
30.9%
87
CCO '21 P2 - Weird Numeral System
CCO
17p
12.1%
87
CCO '03 P5 - Longest Substring
CCO
7p
15.8%
86
CCO '96 P3 - Quadtrees
CCO
15
48.4%
84
CCO '96 P4 - Where's Waldorf?
CCO
7
47.2%
81
CCO '19 P2 - Sirtet
CCO
20p
24.3%
81
CCO '07 P3 - Bowling for Numbers++
CCO
20p
10.5%
80
CCO '03 P6 - Cheap Gas
CCO
20p
13.1%
79
CCO '11 P6 - Biggest (Zero Carbon) Footprint
CCO
15p
12.6%
78
CCO '18 P3 - Fun Palace
CCO
30p
18.1%
76
CCO '09 P6 - A Weighty Problem
CCO
12p
16.1%
76
CCO '13 P5 - Transforming Comets
CCO
15p
19.3%
74
CCO '15 P6 - Eggscavation
CCO
30p
18.5%
70
CCO '16 P6 - Pirates
CCO
25p
20.7%
70
CCO '19 P6 - Bad Codes
CCO
20p
25.6%
69
CCO '08 P2 - King & Weber
CCO
10p
17.6%
69
CCO '15 P3 - Solar Flight
CCO
20p
12.8%
68
CCO '19 P4 - Card Scoring
CCO
25p
15.3%
68
CCO '23 P2 - Real Mountains
CCO
17p
13.8%
68
CCO '12 P6 - The Winds Of War
CCO
12p
40.1%
67
CCO '19 P3 - Winter Driving
CCO
30p
17.1%
66
CCO '04 P2 - Hockey Scores
CCO
12
20.4%
65
CCO '01 P3 - Partitions
CCO
12
33.9%
63
CCO '21 P5 - Bread First Search
CCO
20p
23.0%
63
CCO '16 P3 - Legends
CCO
30p
9.8%
61
CCO '03 P1 - BFed
CCO
10
25.4%
61
CCO '20 P5 - Interval Collection
CCO
25p
16.0%
60
CCO '18 P6 - Flop Sorting
CCO
30p
17.5%
59
CCO '00 P4 - Packet Routing
CCO
7
59.8%
58
CCO '17 P2 - Cartesian Conquest
CCO
20p
9.4%
55
CCO '97 P2 - Alien Invasion
CCO
10
43.4%
54
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