ID NAME QUALITY USERS ACC % DIFFICULTY C I
18164 Atoms in the Lab   19 2436
7
5
328 Bishops   53 6489
15
6
2009 Cryptography   75
314 Digits of e   2584
1
1
24 Small factorials   74 26389
15
9
6236 Matches   2 391
34
1
2906 GCD2   29 4641
11
12
2901 One Geometry Problem   7 1418
5
14
10676 0110SS   11 1308
12
6
54 Julka   70 13715
19
6
5699 The last digit re-visited   25 6027
9
8
3932 Point Connection Game in a Circle   1 596
17
26
3970 Convert to Decimal Base System   1 47
17
17
16034 Minimum Number   1 406
9
1
3023 Binary multiplication   2 202
17
17
18905 Kapti and Balu   1 30
17
17
8676 Digits of Phi (Golden Ratio)   265
270 Digits of Pi   5 5143
13
17
5294 Recurrence   219
34
17
29748 Robin Hood   19
1
1
3362 Setnja   213
10334 SOLDIERS   3 563
1
1
1423 Digits of SQRT(2)   3 2455
12
6
738 Another Counting Problem   211
71 Tree   2 388
9
1
1002 Uncle Jack   9 2620
10
9
235 Very Fast Multiplication   7 538
30
17
6479 The Very Greatest Common Divisor   2 66
26
9
1475 Play with Digit Seven   1 52
17
17

#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