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Hot problems
DWITE '10 R3 #3 - Dominos Tiling
COCI '08 Contest 3 #6 Najkraci
WC '01 P3 - Back to the Future
A Math Contest P5 - Good Arrays
GFSSOC '15 Winter S1 - OR-deal
Counting Subsequences
CCC '11 S1 - English or French?
Problem
Category
Points
AC %
Users ▾
CCC '07 J4 - Anagram Checker
CCC
5
37.2%
2132
CCC '13 S2 - Bridge Transport
CCC
5
26.7%
2059
CCC '10 J2 - Up and Down
CCC
5
21.8%
2055
CCC '20 S1 - Surmising a Sprinter's Speed
CCC
5p
42.8%
2050
CCC '09 S1 - Cool Numbers
CCC
5
22.8%
2027
CCC '15 S2 - Jerseys
CCC
5p
26.7%
1960
CCC '00 J2 - 9966
CCC
3
35.8%
1959
CCC '03 S3 - Floor Plan
CCC
7
27.8%
1956
CCC '96 S1 - Deficient, Perfect, and Abundant
CCC
5
32.3%
1894
CCC '02 S2 - Fraction Action
CCC
5
19.0%
1885
Python Infinite Loop
Uncategorized
7p
17.3%
1879
CCC '11 J2 - Who Has Seen The Wind
CCC
5
25.7%
1867
CCC '12 S3 - Absolutely Acidic
CCC
7
26.7%
1863
CCC '12 S5 - Mouse Journey
CCC
7
45.6%
1820
DMOPC '14 Contest 2 P4 - Deforestation
DMOPC
5p
32.5%
1795
CCC '15 S3 - Gates
CCC
10p
18.7%
1779
CCC '23 J1 - Deliv-e-droid
CCC
3p
55.5%
1734
CCC '17 S3 - Nailed It!
CCC
7p
30.5%
1721
CCC '23 S1 - Trianglane
CCC
5p
32.0%
1721
CCC '12 S2 - Aromatic Numbers
CCC
5
53.4%
1717
CCC '04 J4 - Simple Encryption
CCC
5
51.0%
1711
CCC '07 S3 - Friends
CCC
7
37.5%
1703
3n+1
Uncategorized
3
39.3%
1700
CCC '20 S2 - Escape Room
CCC
10p
12.8%
1696
CCC '05 S2 - Mouse Move
CCC
5
37.3%
1686
CCC '16 J4 - Arrival Time
CCC
5
29.1%
1682
List Minimum (Hard)
Uncategorized
5
35.9%
1670
CCC '23 J2 - Chili Peppers
CCC
3p
53.6%
1638
Another Contest 6 Problem 9 - Obligatory Wood IV Problem
ACC
0p
100.0%
1619
CCC '18 J5 - Choose your own path
CCC
7p
24.1%
1615
CCC '03 J2 - Picture Perfect
CCC
3p
23.9%
1614
COCI '18 Contest 3 #1 Magnus
COCI
5
33.5%
1605
CCC '09 J2 - Old Fishin' Hole
CCC
5
39.1%
1591
CCC '10 S2 - Huffman Encoding
CCC
5
53.6%
1576
CCC '17 J4 - Favourite Times
CCC
5p
23.4%
1572
Triple Fat Ladies
Uncategorized
5
28.7%
1572
CCC '08 S3 - Maze
CCC
7
29.3%
1564
CCC '22 S2 - Good Groups
CCC
5p
26.1%
1563
CCC '11 J4 - Boring Business
CCC
7
27.8%
1510
CCC '01 S1 - Keeping Score
CCC
5
32.7%
1504
CCC '07 S4 - Waterpark
CCC
7
30.9%
1502
CCC '22 J3 - Harp Tuning
CCC
5p
33.2%
1501
CCC '02 S1 - The Students' Council Breakfast
CCC
5
39.6%
1499
IOI '94 P1 - The Triangle
IOI
7p
56.5%
1484
BlueBook - Times Tables
BlueBook
3
54.3%
1481
CCC '98 S1 - Censor
CCC
5
37.5%
1476
CCC '05 J5 - Bananas
CCC
10
21.6%
1471
CCC '06 J3 - Cell-Phone Messaging
CCC
3
41.4%
1468
CCC '15 J5 - π-day
CCC
10p
27.4%
1466
CCC '01 S3 - Strategic Bombing
CCC
7
38.7%
1458
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