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Hot problems
COCI '08 Contest 3 #6 Najkraci
APIO '10 P1 - Commando
CCC '24 J5 - Harvest Waterloo
TSS Club Fair 2017 Problem B
CCC '24 J4 - Troublesome Keys
CCC '04 S2 - TopYodeller
DWITE '10 R3 #3 - Dominos Tiling
Problem
Category
Points ▾
AC %
Users
Google Code Jam '09 Qualification Round Problem C - Welcome to Code Jam
Google Code Jam
7p
19.0%
4
Google Code Jam '10 Qualification Round Problem A - Fair Warning
Google Code Jam
7p
40.0%
2
Google Code Jam '10 Round 1A Problem A - Rotate
Google Code Jam
7
50.0%
5
Google Code Jam '11 Qualification Round Problem B - Candy Splitting
Google Code Jam
7p
57.1%
4
Google Code Jam '12 Round 1A Problem B - Kingdom Rush
Google Code Jam
7p
22.2%
2
Google Code Jam '13 Round 1A Problem A - Bullseye
Google Code Jam
7p
16.7%
4
Google Code Jam '13 Round 1A Problem B - Manage your Energy
Google Code Jam
7p
11.1%
2
Google Code Jam '13 Qualification Round Problem A - Tic-Tac-Toe-Tomek
Google Code Jam
7p
72.7%
6
Google Code Jam '13 Qualification Round Problem B - Lawnmower
Google Code Jam
7p
40.0%
2
Google Code Jam '14 Round 1A Problem A - Charging Chaos
Google Code Jam
7p
66.7%
2
Google Code Jam '15 Round 1A Problem B - Haircut
Google Code Jam
7p
37.5%
3
Google Code Jam '16 Round 1A Problem B - Rank and File
Google Code Jam
7p
66.7%
2
Google Code Jam '18 Qualification Round Problem B - Trouble Sort
Google Code Jam
7p
17.1%
17
Google Code Jam '21 Qualification Round Problem B - Moons and Umbrellas
Google Code Jam
7p
46.2%
6
Google Code Jam '21 Qualification Round Problem C - Reversort Engineering
Google Code Jam
7p
27.5%
9
Google Code Jam '21 Round 1A Problem A - Append Sort
Google Code Jam
7p
35.0%
5
Waterloo 2001 Winter D - Division
Waterloo Local
7
21.1%
4
Waterloo 2001 Winter B - Tight words
Waterloo Local
7
66.7%
4
Waterloo 2013 Fall B - Java vs. Scheme Smackdown
Waterloo Local
7
17.6%
3
Waterloo 2001 Fall 1 E - A Multiplication Game
Waterloo Local
7
16.1%
3
UACC 1 P3 - Cheeky Checkers
Uncategorized
7
60.1%
143
DMOPC '22 Contest 5 P2 - Absolutely Even
DMOPC
7p
19.3%
164
EGOI '23 P1 - Inflation
EGOI
7p
27.9%
135
Waterloo 2023 Fall D - Reptilian Communism
Waterloo Local
7
25.4%
26
Amplitude Hackathon '23 Problem 4 - Frequency Queries
Uncategorized
7p
15.3%
16
Amplitude Hackathon '23 Problem 5 - Partition Assignment
Uncategorized
7p
22.5%
19
WOSS Dual Olympiad 2023 Team Round P2: Holding Eggnog
Uncategorized
7
35.3%
26
COCI '23 Contest 2 #2 Pingvin
COCI
7p
30.1%
36
WOSS Dual Olympiad 2023 J3/S1: Moving Sand
Uncategorized
7
38.2%
114
OTHS Coding Competition 1 (Mock CCC) J4 - Railgun
Uncategorized
7p
23.4%
169
Mock CCC '24 Contest 1 S2 - Owen the Toucan
Mock CCC
7p
33.1%
188
UHCC1 P5 - Binary Triangles
Uncategorized
7p
30.2%
40
UHCC1 P4 - Manhattan Distance
Uncategorized
7
19.2%
42
COCI '23 Contest 4 #2 Knjige
COCI
7p
22.3%
40
CCC '24 J5 - Harvest Waterloo
CCC
7p
37.7%
349
ECOO '13 R1 P1 - Take a Number
ECOO
5p
27.2%
1207
ECOO '13 R1 P2 - The Luhn Algorithm
ECOO
5p
47.7%
366
CCC '96 S1 - Deficient, Perfect, and Abundant
CCC
5
32.3%
1894
CCC '13 S1 - From 1987 to 2013
CCC
5
45.8%
3925
CCC '14 S1 - Party Invitation
CCC
5
47.1%
3527
CCC '14 S2 - Assigning Partners
CCC
5
33.3%
2845
CCC '13 J4 - Time on task
CCC
5
44.5%
3017
Lexicographically Least Substring
Uncategorized
5
46.0%
616
ECOO '14 R1 P1 - Martian Time
ECOO
5p
26.5%
76
List Minimum (Hard)
Uncategorized
5
35.9%
1667
The Mirror
Uncategorized
5
33.3%
678
German Nouns
Uncategorized
5
56.7%
433
Next Prime
Classics
5
19.9%
2185
CCC '98 S1 - Censor
CCC
5
37.5%
1476
Encode
Uncategorized
5
28.5%
246
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