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Random
Hot problems
CCC '24 S2 - Heavy-Light Composition
Educational DP Contest AtCoder G - Longest Path
DWITE '10 R3 #3 - Dominos Tiling
EGOI '23 P4 - Bikes vs Cars
Linked List
CCC '20 S4 - Swapping Seats
A Math Contest P5 - Good Arrays
Problem
Category
Points
AC %
Users ▾
CCO '05 P1 - Number Matrix
CCO
10
24.2%
161
CCO '98 P1 - Fibonacci Numbers
CCO
7
26.2%
158
CCO Preparation Test 1 P3 - K-th Rank Student
Mock CCO
17p
34.6%
154
CCO '21 P1 - Swap Swap Sort
CCO
17p
16.5%
152
CCO '10 P6 - Shuffle
CCO
10
35.4%
150
CCO '12 P4 - Editor Distance
CCO
10
33.6%
143
CCO '16 P5 - Zombie Apocalypse
CCO
15p
19.1%
141
CCO '06 P1 - CN Tower
CCO
5
25.5%
141
CCO Preparation Test 6 P3 - HopScotch
Mock CCO
20p
23.1%
140
CCO '22 P1 - Alternating Heights
CCO
12p
27.4%
138
CCO '19 P5 - Marshmallow Molecules
CCO
15p
26.6%
128
CCO '18 P5 - Boring Lectures
CCO
20p
19.2%
127
CCO '04 P1 - Scribble
CCO
5
42.8%
126
CCO '18 P2 - Wrong Answer
CCO
12p
15.6%
118
CCO Preparation Test 3 P2 - Packing Up
Mock CCO
25p
14.9%
117
CCO '04 P5 - Jengaism
CCO
7
31.8%
116
CCO '11 P1 - Putnam
CCO
7
27.6%
108
CCO '08 P1 - Moving Day
CCO
7p
30.5%
106
CCOQR '16 - Through A Maze Darkly
CCC
20p
18.4%
104
CCO '22 P2 - Rainy Markets
CCO
17p
18.6%
104
CCO '12 P3 - Mhocskian Languages
CCO
20p
49.6%
103
CCO '15 P5 - Timpanist
CCO
20p
36.5%
102
DMPG '16 B3 - CCO
DMOPC
5
41.8%
102
CCO '02 P5 - Connect The Campus
CCO
12
31.0%
101
CCO '17 P3 - Vera and Modern Art
CCO
30p
13.9%
93
CCO '20 P4 - Travelling Salesperson
CCO
25p
19.6%
92
CCO '05 P4 - Primed Sequences
CCO
12p
12.6%
92
CCO '13 P4 - A Romantic Movie Outing
CCO
20p
23.5%
91
CCO '03 P5 - Longest Substring
CCO
7p
16.0%
91
CCO '16 P2 - Splitting Hares
CCO
15p
14.2%
89
CCO '96 P2 - SafeBreaker
CCO
10
36.2%
89
CCO '19 P1 - Human Error
CCO
10p
30.4%
88
CCO '14 P5 - Early Exam Evacuation
CCO
20p
23.3%
87
CCO '21 P2 - Weird Numeral System
CCO
17p
12.1%
87
CCO '19 P2 - Sirtet
CCO
20p
23.6%
85
CCO '96 P3 - Quadtrees
CCO
15
48.4%
84
CCO '96 P4 - Where's Waldorf?
CCO
7
47.2%
81
CCO '07 P3 - Bowling for Numbers++
CCO
20p
10.5%
80
CCO '03 P6 - Cheap Gas
CCO
20p
13.1%
79
CCO '11 P6 - Biggest (Zero Carbon) Footprint
CCO
15p
12.6%
78
Mock CCO '18 Contest 1 Problem 6 - A Combining Problem
Mock CCO
15p
17.6%
78
CCO '18 P3 - Fun Palace
CCO
30p
17.6%
76
CCO '09 P6 - A Weighty Problem
CCO
12p
16.1%
76
CCO '13 P5 - Transforming Comets
CCO
15p
19.3%
74
CCO '15 P6 - Eggscavation
CCO
30p
18.5%
70
CCO '16 P6 - Pirates
CCO
25p
20.5%
70
Mock CCO '19 Contest 2 Problem 1 - A Dynamic Connectivity Problem
Mock CCO
15p
31.3%
70
CCO '19 P6 - Bad Codes
CCO
20p
25.6%
69
CCO '08 P2 - King & Weber
CCO
10p
17.6%
69
CCO '23 P2 - Real Mountains
CCO
17p
13.2%
69
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