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Random
Hot problems
COCI '08 Contest 3 #2 Kemija
DWITE '10 R3 #3 - Dominos Tiling
CCC '24 J3 - Bronze Count
Problem
Category
Points
AC %
Users ▾
COCI '06 Contest 1 #2 Herman
COCI
5
42.1%
655
CCC '10 S3 - Firehose
CCC
15p
18.6%
651
DWITE '07 R1 #1 - Vanilla Primes
DWITE
3
24.6%
651
Longest Increasing Subsequence
Uncategorized
7
29.5%
651
Another Contest 6 Problem 2 - A Plus B (Easy)
ACC
0p
37.6%
647
Facebook Hacker Cup '15 Round 1 P1 - Homework
FHC
10
34.0%
643
CCCJQR P1
Seasonal
0
72.6%
642
COCI '09 Contest 1 #1 Note
COCI
3
52.5%
640
COCI '08 Contest 3 #1 Pet
COCI
5
57.3%
633
Another Contest 5 Problem 1 - Goat Fence
ACC
3p
27.0%
631
Mock CCC '19 Contest 1 S1 - Pusheen's Report Card
Mock CCC
3p
41.3%
630
Educational DP Contest AtCoder E - Knapsack 2
Uncategorized
7
23.5%
627
CCCHK '08 J3 - Phone book
CCC
5p
34.6%
625
CCC '09 S5 - Wireless
CCC
12p
34.8%
622
CCC '00 S3 - Surfing
CCC
7
17.5%
621
ECOO '18 R1 P1 - Willow's Wild Ride
ECOO
5p
27.4%
621
CCO '14 P1 - Troyangles
CCO
10p
37.7%
620
DMOPC '17 Contest 1 P1 - Fujō Neko
DMOPC
5p
25.8%
620
COCI '07 Contest 2 #1 Bijele
COCI
3
64.3%
619
Chocolate Bar
Uncategorized
5
51.8%
619
Lexicographically Least Substring
Uncategorized
5
46.0%
616
CCC '04 S3 - Spreadsheet
CCC
10
27.0%
614
CCCHK '15 J3 - Queens can't attack me!
CCC
5
51.1%
613
Mock CCC '18 Contest 3 J1 - A Sum Problem
Mock CCC
3p
61.2%
604
DMOPC '14 Contest 2 P3 - Sawmill
DMOPC
7p
36.8%
602
CCC '24 J1 - Conveyor Belt Sushi
CCC
3p
77.1%
602
SAC '22 Code Challenge 1 P1 - That Teacher
SAC Coding Challenge
3
69.0%
600
Mock CCC '20 Contest 1 J2 - A Simplex Problem
Mock CCC
3p
52.0%
595
COCI '06 Contest 3 #1 Patuljci
COCI
5
60.0%
593
Hello, World! (Hard)
Uncategorized
0
6.5%
593
Back From Summer '17 P2: Crayola Lightsaber
Seasonal
7
25.2%
590
An Animal Contest 5 P1 - Bamboo Cookies
AAC
3p
46.5%
590
COCI '08 Contest 2 #3 Perket
COCI
7
47.2%
586
BlueBook - Find the Character
BlueBook
3
38.8%
586
DMOPC '19 Contest 6 P0 - Trivial Math
DMOPC
3
64.8%
585
CCC '21 S4 - Daily Commute
CCC
12p
26.0%
585
COCI '06 Contest 1 #4 Slikar
COCI
10
24.1%
582
CCC '05 J4 - Cross Spiral
CCC
7p
32.6%
581
CCC '16 S5 - Circle of Life
CCC
20p
22.5%
578
CCC '18 S4 - Balanced Trees
CCC
15p
16.9%
576
BlueBook - Interest
BlueBook
3
28.5%
575
CCO '18 P1 - Geese vs. Hawks
CCO
10p
37.6%
574
Mock CCC '22 Contest 2 J2 - Snowboarding Championship
Mock CCC
3
35.7%
570
CCC '96 S4 - When in Rome
CCC
10
33.0%
569
Mock CCC '18 Contest 5 J1 - Looking for the CCC
Mock CCC
3p
44.6%
569
WC '17 Contest 1 J1 - Canadian Accent
Woburn Challenge
3
66.0%
566
BlueBook - Prime
BlueBook
3
32.5%
564
DMOPC '18 Contest 1 P0 - Sorting
DMOPC
3
46.7%
561
Mock CCC '23 Contest 1 J2 - Healthy Schedule
Mock CCC
3
38.3%
561
DMOPC '16 Contest 4 P1 - Fast Exponents
DMOPC
5p
26.2%
558
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