ID NAME QUALITY USERS ACC % DIFFICULTY C I
18164 Atoms in the Lab   19 2545
7
5
328 Bishops   56 6642
15
6
2009 Cryptography   75
314 Digits of e   2620
1
1
24 Small factorials   76 27420
14
9
6236 Matches   2 394
34
1
2906 GCD2   30 4778
11
11
2901 One Geometry Problem   7 1441
5
14
10676 0110SS   12 1355
12
6
54 Julka   76 14152
19
6
5699 The last digit re-visited   27 6185
9
9
3932 Point Connection Game in a Circle   1 605
17
26
3970 Convert to Decimal Base System   1 47
17
17
16034 Minimum Number   3 412
13
1
3023 Binary multiplication   2 202
17
17
18905 Kapti and Balu   1 30
17
17
8676 Digits of Phi (Golden Ratio)   267
270 Digits of Pi   6 5235
11
19
5294 Recurrence   224
34
17
29748 Robin Hood   19
1
1
3362 Setnja   218
10334 SOLDIERS   4 570
6
1
1423 Digits of SQRT(2)   3 2472
12
6
738 Another Counting Problem   213
71 Tree   2 388
9
1
1002 Uncle Jack   9 2648
9
8
235 Very Fast Multiplication   7 593
32
21
6479 The Very Greatest Common Divisor   2 67
26
9
1475 Play with Digit Seven   2 58
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