ID NAME QUALITY USERS ACC % DIFFICULTY C I
18164 Atoms in the Lab   19 2604
7
5
328 Bishops   58 6742
15
6
2009 Cryptography   75
314 Digits of e   2650
1
1
24 Small factorials   78 27849
14
8
6236 Matches   2 396
34
1
2906 GCD2   30 4843
11
11
2901 One Geometry Problem   7 1452
5
14
10676 0110SS   12 1382
12
6
54 Julka   79 14366
19
6
5699 The last digit re-visited   28 6257
9
9
3932 Point Connection Game in a Circle   1 606
17
26
3970 Convert to Decimal Base System   1 47
17
17
16034 Minimum Number   3 414
13
1
3023 Binary multiplication   2 206
17
17
18905 Kapti and Balu   1 30
17
17
8676 Digits of Phi (Golden Ratio)   276
270 Digits of Pi   6 5267
11
19
5294 Recurrence   225
34
17
29748 Robin Hood   19
1
1
3362 Setnja   219
10334 SOLDIERS   4 575
6
1
1423 Digits of SQRT(2)   3 2490
12
6
738 Another Counting Problem   213
71 Tree   2 391
9
1
1002 Uncle Jack   9 2656
9
8
235 Very Fast Multiplication   7 618
32
21
6479 The Very Greatest Common Divisor   2 70
26
9
1475 Play with Digit Seven   2 60
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