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PROBLEMS
STATUS
RANKS
DISCUSS
CONTESTS
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Classical
Challenge
Partial
Tutorial
Riddle
Basics
#tags
ID
NAME
QUALITY
USERS
ACC %
DIFFICULTY
C
I
4580
ABCDEF
218
7848
14
16
7386
Activities
62
1434
16
19
28404
Ada and Field
33
564
21
17
297
Aggressive cows
1072
45359
16
23
15454
How to Handle the Fans
39
1521
12
11
4560
The Double HeLiX
147
8891
11
10
28407
Busqueda Binaria
493
1
1
28467
Búsqueda Binaria 2
1
345
27380
Painting Hat
6
252
11
12
19301
Operators (new ver)
3
42
38
17
43
Copying Books
45
2798
19
19
36671
Bipartite Permutation (Hard)
6
52
32
34
14742
Building Bridges(HARD)
10
449
14
17
6168
Building Bridges
27
1652
11
17
110
Fill the Cisterns
29
1412
21
20
5296
Air Combat
-1
63
34
35669
Consecutive Letters
7
524
17
20
13780
Audition
18
648
17
17
6956
IOI2009 Mecho
3
165
28
23
10810
Its a Murder!
55
2390
16
17
27039
Assembly line
17
520
17
14
11814
Eko
171
16022
13
13
5161
Factorial vs Power
14
1129
13
15
5970
Finding Primes
22
1337
16
15
18530
Font Size
7
201
15
5
5978
Frequent Prime Ranges
10
709
14
14
18185
Give Away
33
1181
20
19
2738
Number Guessing Game
42
4630
8
13
9734
Hacking the random number generator
62
5842
8
6
4200
Hamster flight
13
1151
5
13
37921
Birthday Present
3
38
42
34
36951
HowManyLis
7
148
21
22
8002
Horrible Queries
397
10978
19
18
37465
Do you know Factorials
1
8
18247
Arrangement Validity
11
218
17
21
4415
Power of Integer
1
272
17
26
8985
Line up
19
402
16
17
1431
Projections Of A Polygon
2
119
12
6
36667
Solution to all the problems
13
149
15
11
20063
Large subsequence Problem
20
446
10
14
34356
Ludic Numbers (medium)
5
59
36
39
3975
Most Servings Meal
8
351
28
28
148
Land for Motorways
3
210
17
17
34479
Möbius function zero distribution
4
16
6
17
4061
Polygon
4
212
21
17
4483
Roads Repair
7
180
20
23
27321
Increasing numbers
17
559
13
19
2905
Not a Triangle
93
5031
11
11
25024
Nth Prime
7
104
34
39
12151
Pizzamania
28
2161
5
4
#binary-search
Binary search algorithm finds the position of a target value within a sorted array