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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
7907
14
16
7386
Activities
62
1442
16
19
28404
Ada and Field
33
574
21
17
297
Aggressive cows
1075
47028
16
23
15454
How to Handle the Fans
39
1529
12
11
4560
The Double HeLiX
147
8956
11
10
28407
Busqueda Binaria
509
1
1
28467
Búsqueda Binaria 2
1
355
27380
Painting Hat
6
256
11
12
19301
Operators (new ver)
3
46
38
17
43
Copying Books
45
2832
19
19
36671
Bipartite Permutation (Hard)
6
52
32
34
14742
Building Bridges(HARD)
10
451
14
17
6168
Building Bridges
27
1660
11
17
110
Fill the Cisterns
29
1421
21
20
5296
Air Combat
-1
68
34
35669
Consecutive Letters
8
566
17
20
13780
Audition
18
654
17
17
6956
IOI2009 Mecho
3
167
28
23
10810
Its a Murder!
56
2396
16
16
27039
Assembly line
17
549
17
14
11814
Eko
172
16557
14
14
5161
Factorial vs Power
14
1137
13
15
5970
Finding Primes
22
1343
16
15
18530
Font Size
7
205
15
5
5978
Frequent Prime Ranges
10
715
14
14
18185
Give Away
34
1275
20
19
2738
Number Guessing Game
42
4631
8
13
9734
Hacking the random number generator
62
5876
8
6
4200
Hamster flight
13
1158
5
13
37921
Birthday Present
3
40
42
34
36951
HowManyLis
7
156
21
22
8002
Horrible Queries
399
11106
19
18
37465
Do you know Factorials
1
14
18247
Arrangement Validity
11
222
17
21
4415
Power of Integer
1
274
17
26
8985
Line up
19
410
16
17
1431
Projections Of A Polygon
2
120
12
6
36667
Solution to all the problems
13
152
15
11
20063
Large subsequence Problem
20
451
10
14
34356
Ludic Numbers (medium)
5
60
36
39
3975
Most Servings Meal
8
354
28
28
148
Land for Motorways
3
214
17
21
34479
Möbius function zero distribution
4
20
6
17
4061
Polygon
4
215
21
17
4483
Roads Repair
7
182
20
23
27321
Increasing numbers
17
572
13
19
2905
Not a Triangle
93
5047
11
11
25024
Nth Prime
7
110
34
39
12151
Pizzamania
28
2181
5
4
#binary-search
Binary search algorithm finds the position of a target value within a sorted array