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Hot problems
CCC '23 J3 - Special Event
CCC '24 S2 - Heavy-Light Composition
Problem
Category
Points
AC %
▴
Users
Age Demographic
Uncategorized
5
18.9%
112
CCO '22 P2 - Rainy Markets
CCO
17p
18.6%
104
CCO '22 P3 - Double Attendance
CCO
25p
7.4%
28
NOIP '99 P2 - Palindrome Numbers
China NOI
7p
14.1%
25
CCO '22 P4 - Bi-ing Lottery Treekets
CCO
20p
20.5%
30
CCO '22 P5 - Phone Plans
CCO
20p
12.8%
33
NOIP '99 Junior P1 - Cantor Table
China NOI
5p
42.9%
15
NOIP '99 P3 - Traveller's Budget
China NOI
12p
11.4%
13
NOIP '99 P1 - Missile Interception
China NOI
12p
39.8%
40
NOIP '99 P4 - Stamp Face Value Design
China NOI
12p
10.5%
9
Lemon
Uncategorized
10
33.5%
15
A Math Contest P5 - Good Arrays
Uncategorized
7p
29.8%
130
A Math Contest P11 - Weak Goldbach's Conjecture
Uncategorized
15
23.9%
58
A Math Contest P2 - Subsequence Sum
Uncategorized
5
29.2%
343
A Math Contest P10 - Tricky Multisets
Uncategorized
12
25.7%
48
A Math Contest P7 - Factors
Uncategorized
10
29.2%
130
A Math Contest P1 - Arrays
Uncategorized
5
32.1%
249
A Math Contest P14 - Choosing Marbles
Uncategorized
25p
21.9%
38
Adaptive Mechanized Calcium Chlorohypochlorite
Uncategorized
25
15.2%
9
A Math Contest P4 - Circle Cutting
Uncategorized
7
40.9%
105
A Math Contest P13 - Ways
Uncategorized
17
18.9%
28
Pie
Uncategorized
3
61.5%
168
A Math Contest P12 - Triangles
Uncategorized
17
29.5%
20
A Math Contest P8 - Permutation Counting
Uncategorized
12
36.6%
62
Fair Competition
Olympiads School
5
32.7%
121
Lemon Game
Olympiads School
7
28.6%
43
A Math Contest P16 - Morbius vs. Suibom
Uncategorized
25
18.2%
20
APIO '22 P3 - Permutation
APIO
20p
9.8%
12
Rule of Lemons
Uncategorized
10
16.7%
5
A Math Contest P9 - Buy Some Get Some
Uncategorized
12
27.1%
55
A Math Contest P17 - Heatwaves
Uncategorized
45
36.4%
3
A Math Contest P6 - Global Maximum
Uncategorized
10
28.6%
75
APIO '22 P2 - Game
APIO
25p
1.9%
3
SGS Programming Challenge P4 - Toy in Psychology Class
Uncategorized
17p
8.0%
14
NOIP '20 P1 - Drainage System
China NOI
10p
10.6%
20
NOIP '20 P2 - String Matching
China NOI
12p
13.5%
10
NOIP '20 P3 - Game of Moving Ball
China NOI
15p
12.3%
6
NOI '02 P2 - Naughty Kid
China NOI
15p
22.5%
14
Building
Uncategorized
10p
24.5%
49
SGS Programming Challenge P3 - Tree in Biology Class
Uncategorized
15p
16.5%
39
Good Sets
Uncategorized
10p
27.2%
32
Baltic OI '04 P1 - Ships
Baltic OI
7p
14.2%
12
DMOPC '22 Contest 1 P6 - Linear Swap
DMOPC
30p
7.8%
9
Baltic OI '04 P2 - Scales
Baltic OI
10p
44.4%
4
Baltic OI '04 P3 - Sequence
Baltic OI
30p
30.8%
7
Baltic OI '04 P4 - Repeats
Baltic OI
30p
50.0%
3
JOI '21 Open P1 - Crossing
JOI
20p
42.9%
9
JOI '21 Open P2 - Financial Report
JOI
25p
34.0%
13
JOI '21 Spring Camp Day 1 P1 - Aerobatics
JOI
45p
0.0%
0
Baltic OI '12 P6 - Tiny
Baltic OI
30p
0.0%
0
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