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Random
Hot problems
CCC '24 S2 - Heavy-Light Composition
COCI '11 Contest 5 #2 Eko
String Finding
APIO '09 P3 - The Great ATM Robbery
CCO '07 P2 - Snowflakes
CCC '24 J4 - Troublesome Keys
Problem
Category
Points
AC %
Users ▴
Hailstone Numbers
Uncategorized
3
57.0%
807
CCC '23 S2 - Symmetric Mountains
CCC
7p
26.6%
813
CCC '05 S4 - Pyramid Message Scheme
CCC
10
35.7%
817
Mock CCC '20 Contest 1 J1 - A Rage Tree Problem
Mock CCC
3p
48.3%
823
IOI '00 P1 - Palindrome
IOI
10p
18.5%
829
Educational DP Contest AtCoder C - Vacation
Uncategorized
7
60.0%
829
BlueBook - Leap Year
BlueBook
3
37.8%
836
Longest Common Subsequence
Classics
7
40.5%
837
CCC '20 S3 - Searching for Strings
CCC
12p
8.9%
841
ECOO '17 R1 P1 - Munch 'n' Brunch
ECOO
5p
18.1%
843
CCCHK '08 J2 - Lucky Number
CCC
3
26.8%
845
List Minimum (Easy)
Uncategorized
3p
11.9%
850
ACSL '09 Practice P4 - Rank
Uncategorized
7
45.9%
850
CCCHK '15 J1 - Rock-paper-scissors
CCC
3
51.7%
852
DMOPC '14 Contest 3 P1 - Not Enough Users!
DMOPC
3p
48.6%
857
Educational DP Contest AtCoder B - Frog 2
Uncategorized
7
43.0%
857
ACM U of T Tryouts C1 A - Rock Paper Scissors Fox
ICPC
3
49.3%
859
CCC '07 S5 - Bowling for Numbers
CCC
10p
29.9%
866
COCI '06 Contest 2 #2 ABC
COCI
3
45.6%
867
PEG Test '14 - Water
Uncategorized
3
54.6%
870
BlueBook - Direction
BlueBook
3
40.8%
871
DMOPC '14 Contest 1 P3 - New Students
DMOPC
3p
37.6%
874
Disjoint Set Test
Data Structure Tests
10
37.0%
884
CCC '02 S4 - Bridge Crossing
CCC
10p
37.2%
884
IOI '04 P4 - Phidias
IOI
10p
53.5%
885
CCC '08 J4 - From Prefix to Postfix
CCC
7
42.8%
888
Binary
Uncategorized
5
24.1%
888
GFSSOC '14 Winter J1 - Flying Plushies
GFSSOC
3p
50.6%
888
CCC '09 S2 - Lights Going On and Off
CCC
10
40.5%
899
ECOO '19 R1 P1 - Free Shirts
ECOO
5p
31.2%
902
Prime Factorization
Uncategorized
5
25.2%
903
The Cosmic Era P2 - Uneven Sand
Uncategorized
5
24.5%
912
CCC '01 S2 - Spirals
CCC
5
41.2%
912
Back To School '16: Harambe
Seasonal
3p
30.5%
913
CCC '16 S4 - Combining Riceballs
CCC
15p
28.8%
935
STNBD P1 - Ren Ashbell
Uncategorized
3p
29.3%
944
Mock CCC '19 Contest 1 J1 - Pusheen's Report Card
Mock CCC
3p
36.1%
962
BlueBook - Exact Divisors
BlueBook
3
64.2%
978
CCO '07 P2 - Snowflakes
CCO
10
14.5%
979
COCI '12 Contest 5 #1 Ljestvica
COCI
5p
19.4%
979
ACM U of T Tryouts C0 A - Max Flow
ICPC
3
60.4%
984
The Cosmic Era P3 - Battle Positions
Uncategorized
7
30.5%
985
CCC '99 S1 - Card Game
CCC
5
31.3%
998
CCC '11 J5 - Unfriend
CCC
7
46.8%
1003
CCC '21 S3 - Lunch Concert
CCC
10p
24.5%
1017
CCC '97 S1 - Sentences
CCC
5
29.4%
1019
LKP '18 Contest 2 P1 - Food Lines
Uncategorized
3
37.7%
1027
COCI '18 Contest 4 #1 Elder
COCI
5p
36.8%
1032
CCC '09 S4 - Shop and Ship
CCC
10
21.0%
1033
Educational DP Contest AtCoder D - Knapsack 1
Uncategorized
7
38.7%
1043
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