ID NAME QUALITY USERS ACC % DIFFICULTY C I
18164 Atoms in the Lab   28 3136
7
5
328 Bishops   73 7585
14
6
2009 Cryptography   1 78
1
34
314 Digits of e   3 2815
1
1
24 Small factorials   122 32987
15
9
6236 Matches   5 419
28
6
36563 Hard Fibonacci   4 12
12
17
2906 GCD2   48 5572
12
10
2901 One Geometry Problem   8 1544
5
13
10676 0110SS   22 1600
12
8
54 Julka   131 16623
19
6
5699 The last digit re-visited   35 6843
9
9
3932 Point Connection Game in a Circle   2 674
12
17
3970 Convert to Decimal Base System   48
17
17
16034 Minimum Number   4 457
11
1
3023 Binary multiplication   2 220
17
17
35954 New Data Type   58
6
6
18905 Kapti and Balu   1 31
17
17
8676 Digits of Phi (Golden Ratio)   1 285
17
17
270 Digits of Pi   10 5545
9
16
5294 Recurrence   1 243
34
17
29748 Robin Hood   25
1
1
3362 Setnja   224
10334 SOLDIERS   5 617
11
4
1423 Digits of SQRT(2)   4 2605
12
6
738 Another Counting Problem   217
71 Tree   2 399
12
9
1002 Uncle Jack   10 2804
10
9
235 Very Fast Multiplication   18 891
27
22
6479 The Very Greatest Common Divisor   2 76
26
9
1475 Play with Digit Seven   4 74
17
9

#big-numbers

The problem involves arbitrary precision arithmetic

https://en.wikipedia.org/wiki/Arbitrary-precision_arithmetic https://en.wikipedia.org/wiki/Karatsuba_algorithm - efficient multiplication algorithm https://en.wikipedia.org/wiki/Toom%E2%80%93Cook_multiplication - as above https://en.wikipedia.org/wiki/Sch%C3%B6nhage%E2%80%93Strassen_algorithm - as above https://en.wikipedia.org/wiki/F%C3%BCrer%27s_algorithm - as above