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Random
Hot problems
Educational DP Contest AtCoder C - Vacation
COCI '14 Contest 5 #3 Traktor
CCCHK '15 J3 - Queens can't attack me!
IOI '04 P4 - Phidias
CCC '10 J2 - Up and Down
IOI '14 Practice Task 1 - Square
CCC '24 J5 - Harvest Waterloo
Problem
Category
Points
AC %
Users ▾
LKP '18 Contest 2 P1 - Food Lines
Uncategorized
3
37.7%
1009
CCC '11 J5 - Unfriend
CCC
7
46.8%
1002
CCC '99 S1 - Card Game
CCC
5
31.3%
993
The Cosmic Era P3 - Battle Positions
Uncategorized
7
30.4%
982
ACM U of T Tryouts C0 A - Max Flow
ICPC
3
60.3%
982
BlueBook - Exact Divisors
BlueBook
3
64.2%
976
COCI '12 Contest 5 #1 Ljestvica
COCI
5p
19.4%
967
CCO '07 P2 - Snowflakes
CCO
10
14.4%
958
Mock CCC '19 Contest 1 J1 - Pusheen's Report Card
Mock CCC
3p
36.5%
954
STNBD P1 - Ren Ashbell
Uncategorized
3p
29.2%
942
CCC '16 S4 - Combining Riceballs
CCC
15p
28.7%
930
Back To School '16: Harambe
Seasonal
3p
30.5%
911
CCC '01 S2 - Spirals
CCC
5
41.2%
908
Prime Factorization
Uncategorized
5
25.2%
899
CCC '09 S2 - Lights Going On and Off
CCC
10
40.5%
897
The Cosmic Era P2 - Uneven Sand
Uncategorized
5
24.4%
896
CCC '08 J4 - From Prefix to Postfix
CCC
7
42.8%
886
Binary
Uncategorized
5
24.1%
886
GFSSOC '14 Winter J1 - Flying Plushies
GFSSOC
3p
50.5%
883
CCC '02 S4 - Bridge Crossing
CCC
10p
37.1%
882
ECOO '19 R1 P1 - Free Shirts
ECOO
5p
31.1%
882
Disjoint Set Test
Data Structure Tests
10
36.9%
881
DMOPC '14 Contest 1 P3 - New Students
DMOPC
3p
37.6%
873
BlueBook - Direction
BlueBook
3
40.8%
869
PEG Test '14 - Water
Uncategorized
3
54.6%
868
COCI '06 Contest 2 #2 ABC
COCI
3
45.6%
867
CCC '07 S5 - Bowling for Numbers
CCC
10p
29.9%
864
ACM U of T Tryouts C1 A - Rock Paper Scissors Fox
ICPC
3
49.3%
857
DMOPC '14 Contest 3 P1 - Not Enough Users!
DMOPC
3p
48.6%
856
IOI '04 P4 - Phidias
IOI
10p
54.6%
856
CCCHK '15 J1 - Rock-paper-scissors
CCC
3
51.7%
849
List Minimum (Easy)
Uncategorized
3p
11.9%
846
CCCHK '08 J2 - Lucky Number
CCC
3
26.8%
841
Longest Common Subsequence
Classics
7
40.5%
834
CCC '20 S3 - Searching for Strings
CCC
12p
8.9%
834
ECOO '17 R1 P1 - Munch 'n' Brunch
ECOO
5p
18.0%
833
BlueBook - Leap Year
BlueBook
3
37.8%
833
ACSL '09 Practice P4 - Rank
Uncategorized
7
46.1%
829
Educational DP Contest AtCoder B - Frog 2
Uncategorized
7
43.7%
826
CCC '05 S4 - Pyramid Message Scheme
CCC
10
35.7%
816
Mock CCC '20 Contest 1 J1 - A Rage Tree Problem
Mock CCC
3p
48.4%
816
IOI '00 P1 - Palindrome
IOI
10p
18.4%
815
Educational DP Contest AtCoder C - Vacation
Uncategorized
7
59.9%
812
CCC '23 S2 - Symmetric Mountains
CCC
7p
26.4%
808
Hailstone Numbers
Uncategorized
3
57.1%
805
VPEX P0 - Pizza
Uncategorized
3p
40.2%
804
DMOPC '13 Contest 1 P4 - AFK
DMOPC
7p
26.0%
802
GFSSOC '15 Fall J4 - Marathon
GFSSOC
7p
39.8%
802
CCCHK '08 J1 - Best fish
CCC
3
38.0%
801
BlueBook - Equation
BlueBook
3
26.1%
796
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