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Hot problems
CCC '24 J4 - Troublesome Keys
COCI '22 Contest 4 #1 7Krokods
CCC '24 S2 - Heavy-Light Composition
CCC '19 J3 - Cold Compress
CCC '24 J5 - Harvest Waterloo
COCI '23 Contest 5 #1 Zlagalica
CCC '24 S3 - Swipe
Problem
Category
Points
AC %
Users ▾
CCC '11 J5 - Unfriend
CCC
7
46.8%
1001
LKP '18 Contest 2 P1 - Food Lines
Uncategorized
3
37.9%
985
CCC '99 S1 - Card Game
CCC
5
31.3%
984
The Cosmic Era P3 - Battle Positions
Uncategorized
7
30.4%
981
ACM U of T Tryouts C0 A - Max Flow
ICPC
3
60.3%
974
BlueBook - Exact Divisors
BlueBook
3
64.1%
973
COCI '12 Contest 5 #1 Ljestvica
COCI
5p
19.5%
958
Mock CCC '19 Contest 1 J1 - Pusheen's Report Card
Mock CCC
3p
36.5%
950
CCO '07 P2 - Snowflakes
CCO
10
14.5%
948
STNBD P1 - Ren Ashbell
Uncategorized
3p
29.2%
942
CCC '16 S4 - Combining Riceballs
CCC
15p
28.7%
925
Back To School '16: Harambe
Seasonal
3p
30.6%
910
CCC '01 S2 - Spirals
CCC
5
41.0%
906
Prime Factorization
Uncategorized
5
25.2%
897
The Cosmic Era P2 - Uneven Sand
Uncategorized
5
24.4%
893
CCC '09 S2 - Lights Going On and Off
CCC
10
40.4%
891
CCC '08 J4 - From Prefix to Postfix
CCC
7
43.0%
884
Binary
Uncategorized
5
24.1%
883
CCC '02 S4 - Bridge Crossing
CCC
10p
37.2%
882
ECOO '19 R1 P1 - Free Shirts
ECOO
5p
31.0%
880
GFSSOC '14 Winter J1 - Flying Plushies
GFSSOC
3p
50.6%
877
Disjoint Set Test
Data Structure Tests
10
36.8%
873
DMOPC '14 Contest 1 P3 - New Students
DMOPC
3p
37.6%
870
BlueBook - Direction
BlueBook
3
40.7%
868
PEG Test '14 - Water
Uncategorized
3
54.5%
865
CCC '07 S5 - Bowling for Numbers
CCC
10p
29.9%
863
COCI '06 Contest 2 #2 ABC
COCI
3
45.4%
857
ACM U of T Tryouts C1 A - Rock Paper Scissors Fox
ICPC
3
49.2%
853
DMOPC '14 Contest 3 P1 - Not Enough Users!
DMOPC
3p
48.6%
851
CCCHK '15 J1 - Rock-paper-scissors
CCC
3
51.7%
843
List Minimum (Easy)
Uncategorized
3p
11.9%
839
IOI '04 P4 - Phidias
IOI
10p
55.1%
837
CCCHK '08 J2 - Lucky Number
CCC
3
26.8%
835
CCC '20 S3 - Searching for Strings
CCC
12p
8.9%
831
BlueBook - Leap Year
BlueBook
3
37.8%
831
ECOO '17 R1 P1 - Munch 'n' Brunch
ECOO
5p
17.9%
820
CCC '05 S4 - Pyramid Message Scheme
CCC
10
35.7%
815
Educational DP Contest AtCoder B - Frog 2
Uncategorized
7
43.8%
813
ACSL '09 Practice P4 - Rank
Uncategorized
7
46.5%
813
Educational DP Contest AtCoder C - Vacation
Uncategorized
7
60.1%
809
IOI '00 P1 - Palindrome
IOI
10p
18.4%
808
Mock CCC '20 Contest 1 J1 - A Rage Tree Problem
Mock CCC
3p
48.4%
805
VPEX P0 - Pizza
Uncategorized
3p
40.2%
803
DMOPC '13 Contest 1 P4 - AFK
DMOPC
7p
26.0%
802
Hailstone Numbers
Uncategorized
3
57.0%
801
CCC '23 S2 - Symmetric Mountains
CCC
7p
25.9%
801
Longest Common Subsequence
Classics
7
40.1%
799
GFSSOC '15 Fall J4 - Marathon
GFSSOC
7p
39.9%
798
CCCHK '08 J1 - Best fish
CCC
3
38.2%
797
BlueBook - Equation
BlueBook
3
26.0%
793
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